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* udf: Propagate errors from udf_truncate_extents()Jan Kara2019-03-183-5/+8
| | | | | | | | Make udf_truncate_extents() properly propagate errors to its callers and let udf_setsize() handle the error properly as well. This lets userspace know in case there's some error when truncating blocks. Signed-off-by: Jan Kara <jack@suse.cz>
* udf: Fix crash on IO error during truncateJan Kara2019-03-181-0/+3
| | | | | | | | | | | | | | When truncate(2) hits IO error when reading indirect extent block the code just bugs with: kernel BUG at linux-4.15.0/fs/udf/truncate.c:249! ... Fix the problem by bailing out cleanly in case of IO error. CC: stable@vger.kernel.org Reported-by: jean-luc malet <jeanluc.malet@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz>
* Merge tag '9p-for-5.1' of git://github.com/martinetd/linuxLinus Torvalds2019-03-175-30/+53
|\ | | | | | | | | | | | | | | | | | | | | | | | | Pull 9p updates from Dominique Martinet: "Here is a 9p update for 5.1; there honestly hasn't been much. Two fixes (leak on invalid mount argument and possible deadlock on i_size update on 32bit smp) and a fall-through warning cleanup" * tag '9p-for-5.1' of git://github.com/martinetd/linux: 9p/net: fix memory leak in p9_client_create 9p: use inode->i_lock to protect i_size_write() under 32-bit 9p: mark expected switch fall-through
| * 9p: use inode->i_lock to protect i_size_write() under 32-bitHou Tao2019-03-035-30/+53
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use inode->i_lock to protect i_size_write(), else i_size_read() in generic_fillattr() may loop infinitely in read_seqcount_begin() when multiple processes invoke v9fs_vfs_getattr() or v9fs_vfs_getattr_dotl() simultaneously under 32-bit SMP environment, and a soft lockup will be triggered as show below: watchdog: BUG: soft lockup - CPU#5 stuck for 22s! [stat:2217] Modules linked in: CPU: 5 PID: 2217 Comm: stat Not tainted 5.0.0-rc1-00005-g7f702faf5a9e #4 Hardware name: Generic DT based system PC is at generic_fillattr+0x104/0x108 LR is at 0xec497f00 pc : [<802b8898>] lr : [<ec497f00>] psr: 200c0013 sp : ec497e20 ip : ed608030 fp : ec497e3c r10: 00000000 r9 : ec497f00 r8 : ed608030 r7 : ec497ebc r6 : ec497f00 r5 : ee5c1550 r4 : ee005780 r3 : 0000052d r2 : 00000000 r1 : ec497f00 r0 : ed608030 Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: ac48006a DAC: 00000051 CPU: 5 PID: 2217 Comm: stat Not tainted 5.0.0-rc1-00005-g7f702faf5a9e #4 Hardware name: Generic DT based system Backtrace: [<8010d974>] (dump_backtrace) from [<8010dc88>] (show_stack+0x20/0x24) [<8010dc68>] (show_stack) from [<80a1d194>] (dump_stack+0xb0/0xdc) [<80a1d0e4>] (dump_stack) from [<80109f34>] (show_regs+0x1c/0x20) [<80109f18>] (show_regs) from [<801d0a80>] (watchdog_timer_fn+0x280/0x2f8) [<801d0800>] (watchdog_timer_fn) from [<80198658>] (__hrtimer_run_queues+0x18c/0x380) [<801984cc>] (__hrtimer_run_queues) from [<80198e60>] (hrtimer_run_queues+0xb8/0xf0) [<80198da8>] (hrtimer_run_queues) from [<801973e8>] (run_local_timers+0x28/0x64) [<801973c0>] (run_local_timers) from [<80197460>] (update_process_times+0x3c/0x6c) [<80197424>] (update_process_times) from [<801ab2b8>] (tick_nohz_handler+0xe0/0x1bc) [<801ab1d8>] (tick_nohz_handler) from [<80843050>] (arch_timer_handler_virt+0x38/0x48) [<80843018>] (arch_timer_handler_virt) from [<80180a64>] (handle_percpu_devid_irq+0x8c/0x240) [<801809d8>] (handle_percpu_devid_irq) from [<8017ac20>] (generic_handle_irq+0x34/0x44) [<8017abec>] (generic_handle_irq) from [<8017b344>] (__handle_domain_irq+0x6c/0xc4) [<8017b2d8>] (__handle_domain_irq) from [<801022e0>] (gic_handle_irq+0x4c/0x88) [<80102294>] (gic_handle_irq) from [<80101a30>] (__irq_svc+0x70/0x98) [<802b8794>] (generic_fillattr) from [<8056b284>] (v9fs_vfs_getattr_dotl+0x74/0xa4) [<8056b210>] (v9fs_vfs_getattr_dotl) from [<802b8904>] (vfs_getattr_nosec+0x68/0x7c) [<802b889c>] (vfs_getattr_nosec) from [<802b895c>] (vfs_getattr+0x44/0x48) [<802b8918>] (vfs_getattr) from [<802b8a74>] (vfs_statx+0x9c/0xec) [<802b89d8>] (vfs_statx) from [<802b9428>] (sys_lstat64+0x48/0x78) [<802b93e0>] (sys_lstat64) from [<80101000>] (ret_fast_syscall+0x0/0x28) [dominique.martinet@cea.fr: updated comment to not refer to a function in another subsystem] Link: http://lkml.kernel.org/r/20190124063514.8571-2-houtao1@huawei.com Cc: stable@vger.kernel.org Fixes: 7549ae3e81cc ("9p: Use the i_size_[read, write]() macros instead of using inode->i_size directly.") Reported-by: Xing Gaopeng <xingaopeng@huawei.com> Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
* | Merge tag 'pidfd-v5.1-rc1' of ↵Linus Torvalds2019-03-161-0/+9
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull pidfd system call from Christian Brauner: "This introduces the ability to use file descriptors from /proc/<pid>/ as stable handles on struct pid. Even if a pid is recycled the handle will not change. For a start these fds can be used to send signals to the processes they refer to. With the ability to use /proc/<pid> fds as stable handles on struct pid we can fix a long-standing issue where after a process has exited its pid can be reused by another process. If a caller sends a signal to a reused pid it will end up signaling the wrong process. With this patchset we enable a variety of use cases. One obvious example is that we can now safely delegate an important part of process management - sending signals - to processes other than the parent of a given process by sending file descriptors around via scm rights and not fearing that the given process will have been recycled in the meantime. It also allows for easy testing whether a given process is still alive or not by sending signal 0 to a pidfd which is quite handy. There has been some interest in this feature e.g. from systems management (systemd, glibc) and container managers. I have requested and gotten comments from glibc to make sure that this syscall is suitable for their needs as well. In the future I expect it to take on most other pid-based signal syscalls. But such features are left for the future once they are needed. This has been sitting in linux-next for quite a while and has not caused any issues. It comes with selftests which verify basic functionality and also test that a recycled pid cannot be signaled via a pidfd. Jon has written about a prior version of this patchset. It should cover the basic functionality since not a lot has changed since then: https://lwn.net/Articles/773459/ The commit message for the syscall itself is extensively documenting the syscall, including it's functionality and extensibility" * tag 'pidfd-v5.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: selftests: add tests for pidfd_send_signal() signal: add pidfd_send_signal() syscall
| * | signal: add pidfd_send_signal() syscallChristian Brauner2019-03-051-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kill() syscall operates on process identifiers (pid). After a process has exited its pid can be reused by another process. If a caller sends a signal to a reused pid it will end up signaling the wrong process. This issue has often surfaced and there has been a push to address this problem [1]. This patch uses file descriptors (fd) from proc/<pid> as stable handles on struct pid. Even if a pid is recycled the handle will not change. The fd can be used to send signals to the process it refers to. Thus, the new syscall pidfd_send_signal() is introduced to solve this problem. Instead of pids it operates on process fds (pidfd). /* prototype and argument /* long pidfd_send_signal(int pidfd, int sig, siginfo_t *info, unsigned int flags); /* syscall number 424 */ The syscall number was chosen to be 424 to align with Arnd's rework in his y2038 to minimize merge conflicts (cf. [25]). In addition to the pidfd and signal argument it takes an additional siginfo_t and flags argument. If the siginfo_t argument is NULL then pidfd_send_signal() is equivalent to kill(<positive-pid>, <signal>). If it is not NULL pidfd_send_signal() is equivalent to rt_sigqueueinfo(). The flags argument is added to allow for future extensions of this syscall. It currently needs to be passed as 0. Failing to do so will cause EINVAL. /* pidfd_send_signal() replaces multiple pid-based syscalls */ The pidfd_send_signal() syscall currently takes on the job of rt_sigqueueinfo(2) and parts of the functionality of kill(2), Namely, when a positive pid is passed to kill(2). It will however be possible to also replace tgkill(2) and rt_tgsigqueueinfo(2) if this syscall is extended. /* sending signals to threads (tid) and process groups (pgid) */ Specifically, the pidfd_send_signal() syscall does currently not operate on process groups or threads. This is left for future extensions. In order to extend the syscall to allow sending signal to threads and process groups appropriately named flags (e.g. PIDFD_TYPE_PGID, and PIDFD_TYPE_TID) should be added. This implies that the flags argument will determine what is signaled and not the file descriptor itself. Put in other words, grouping in this api is a property of the flags argument not a property of the file descriptor (cf. [13]). Clarification for this has been requested by Eric (cf. [19]). When appropriate extensions through the flags argument are added then pidfd_send_signal() can additionally replace the part of kill(2) which operates on process groups as well as the tgkill(2) and rt_tgsigqueueinfo(2) syscalls. How such an extension could be implemented has been very roughly sketched in [14], [15], and [16]. However, this should not be taken as a commitment to a particular implementation. There might be better ways to do it. Right now this is intentionally left out to keep this patchset as simple as possible (cf. [4]). /* naming */ The syscall had various names throughout iterations of this patchset: - procfd_signal() - procfd_send_signal() - taskfd_send_signal() In the last round of reviews it was pointed out that given that if the flags argument decides the scope of the signal instead of different types of fds it might make sense to either settle for "procfd_" or "pidfd_" as prefix. The community was willing to accept either (cf. [17] and [18]). Given that one developer expressed strong preference for the "pidfd_" prefix (cf. [13]) and with other developers less opinionated about the name we should settle for "pidfd_" to avoid further bikeshedding. The "_send_signal" suffix was chosen to reflect the fact that the syscall takes on the job of multiple syscalls. It is therefore intentional that the name is not reminiscent of neither kill(2) nor rt_sigqueueinfo(2). Not the fomer because it might imply that pidfd_send_signal() is a replacement for kill(2), and not the latter because it is a hassle to remember the correct spelling - especially for non-native speakers - and because it is not descriptive enough of what the syscall actually does. The name "pidfd_send_signal" makes it very clear that its job is to send signals. /* zombies */ Zombies can be signaled just as any other process. No special error will be reported since a zombie state is an unreliable state (cf. [3]). However, this can be added as an extension through the @flags argument if the need ever arises. /* cross-namespace signals */ The patch currently enforces that the signaler and signalee either are in the same pid namespace or that the signaler's pid namespace is an ancestor of the signalee's pid namespace. This is done for the sake of simplicity and because it is unclear to what values certain members of struct siginfo_t would need to be set to (cf. [5], [6]). /* compat syscalls */ It became clear that we would like to avoid adding compat syscalls (cf. [7]). The compat syscall handling is now done in kernel/signal.c itself by adding __copy_siginfo_from_user_generic() which lets us avoid compat syscalls (cf. [8]). It should be noted that the addition of __copy_siginfo_from_user_any() is caused by a bug in the original implementation of rt_sigqueueinfo(2) (cf. 12). With upcoming rework for syscall handling things might improve significantly (cf. [11]) and __copy_siginfo_from_user_any() will not gain any additional callers. /* testing */ This patch was tested on x64 and x86. /* userspace usage */ An asciinema recording for the basic functionality can be found under [9]. With this patch a process can be killed via: #define _GNU_SOURCE #include <errno.h> #include <fcntl.h> #include <signal.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/stat.h> #include <sys/syscall.h> #include <sys/types.h> #include <unistd.h> static inline int do_pidfd_send_signal(int pidfd, int sig, siginfo_t *info, unsigned int flags) { #ifdef __NR_pidfd_send_signal return syscall(__NR_pidfd_send_signal, pidfd, sig, info, flags); #else return -ENOSYS; #endif } int main(int argc, char *argv[]) { int fd, ret, saved_errno, sig; if (argc < 3) exit(EXIT_FAILURE); fd = open(argv[1], O_DIRECTORY | O_CLOEXEC); if (fd < 0) { printf("%s - Failed to open \"%s\"\n", strerror(errno), argv[1]); exit(EXIT_FAILURE); } sig = atoi(argv[2]); printf("Sending signal %d to process %s\n", sig, argv[1]); ret = do_pidfd_send_signal(fd, sig, NULL, 0); saved_errno = errno; close(fd); errno = saved_errno; if (ret < 0) { printf("%s - Failed to send signal %d to process %s\n", strerror(errno), sig, argv[1]); exit(EXIT_FAILURE); } exit(EXIT_SUCCESS); } /* Q&A * Given that it seems the same questions get asked again by people who are * late to the party it makes sense to add a Q&A section to the commit * message so it's hopefully easier to avoid duplicate threads. * * For the sake of progress please consider these arguments settled unless * there is a new point that desperately needs to be addressed. Please make * sure to check the links to the threads in this commit message whether * this has not already been covered. */ Q-01: (Florian Weimer [20], Andrew Morton [21]) What happens when the target process has exited? A-01: Sending the signal will fail with ESRCH (cf. [22]). Q-02: (Andrew Morton [21]) Is the task_struct pinned by the fd? A-02: No. A reference to struct pid is kept. struct pid - as far as I understand - was created exactly for the reason to not require to pin struct task_struct (cf. [22]). Q-03: (Andrew Morton [21]) Does the entire procfs directory remain visible? Just one entry within it? A-03: The same thing that happens right now when you hold a file descriptor to /proc/<pid> open (cf. [22]). Q-04: (Andrew Morton [21]) Does the pid remain reserved? A-04: No. This patchset guarantees a stable handle not that pids are not recycled (cf. [22]). Q-05: (Andrew Morton [21]) Do attempts to signal that fd return errors? A-05: See {Q,A}-01. Q-06: (Andrew Morton [22]) Is there a cleaner way of obtaining the fd? Another syscall perhaps. A-06: Userspace can already trivially retrieve file descriptors from procfs so this is something that we will need to support anyway. Hence, there's no immediate need to add another syscalls just to make pidfd_send_signal() not dependent on the presence of procfs. However, adding a syscalls to get such file descriptors is planned for a future patchset (cf. [22]). Q-07: (Andrew Morton [21] and others) This fd-for-a-process sounds like a handy thing and people may well think up other uses for it in the future, probably unrelated to signals. Are the code and the interface designed to permit such future applications? A-07: Yes (cf. [22]). Q-08: (Andrew Morton [21] and others) Now I think about it, why a new syscall? This thing is looking rather like an ioctl? A-08: This has been extensively discussed. It was agreed that a syscall is preferred for a variety or reasons. Here are just a few taken from prior threads. Syscalls are safer than ioctl()s especially when signaling to fds. Processes are a core kernel concept so a syscall seems more appropriate. The layout of the syscall with its four arguments would require the addition of a custom struct for the ioctl() thereby causing at least the same amount or even more complexity for userspace than a simple syscall. The new syscall will replace multiple other pid-based syscalls (see description above). The file-descriptors-for-processes concept introduced with this syscall will be extended with other syscalls in the future. See also [22], [23] and various other threads already linked in here. Q-09: (Florian Weimer [24]) What happens if you use the new interface with an O_PATH descriptor? A-09: pidfds opened as O_PATH fds cannot be used to send signals to a process (cf. [2]). Signaling processes through pidfds is the equivalent of writing to a file. Thus, this is not an operation that operates "purely at the file descriptor level" as required by the open(2) manpage. See also [4]. /* References */ [1]: https://lore.kernel.org/lkml/20181029221037.87724-1-dancol@google.com/ [2]: https://lore.kernel.org/lkml/874lbtjvtd.fsf@oldenburg2.str.redhat.com/ [3]: https://lore.kernel.org/lkml/20181204132604.aspfupwjgjx6fhva@brauner.io/ [4]: https://lore.kernel.org/lkml/20181203180224.fkvw4kajtbvru2ku@brauner.io/ [5]: https://lore.kernel.org/lkml/20181121213946.GA10795@mail.hallyn.com/ [6]: https://lore.kernel.org/lkml/20181120103111.etlqp7zop34v6nv4@brauner.io/ [7]: https://lore.kernel.org/lkml/36323361-90BD-41AF-AB5B-EE0D7BA02C21@amacapital.net/ [8]: https://lore.kernel.org/lkml/87tvjxp8pc.fsf@xmission.com/ [9]: https://asciinema.org/a/IQjuCHew6bnq1cr78yuMv16cy [11]: https://lore.kernel.org/lkml/F53D6D38-3521-4C20-9034-5AF447DF62FF@amacapital.net/ [12]: https://lore.kernel.org/lkml/87zhtjn8ck.fsf@xmission.com/ [13]: https://lore.kernel.org/lkml/871s6u9z6u.fsf@xmission.com/ [14]: https://lore.kernel.org/lkml/20181206231742.xxi4ghn24z4h2qki@brauner.io/ [15]: https://lore.kernel.org/lkml/20181207003124.GA11160@mail.hallyn.com/ [16]: https://lore.kernel.org/lkml/20181207015423.4miorx43l3qhppfz@brauner.io/ [17]: https://lore.kernel.org/lkml/CAGXu5jL8PciZAXvOvCeCU3wKUEB_dU-O3q0tDw4uB_ojMvDEew@mail.gmail.com/ [18]: https://lore.kernel.org/lkml/20181206222746.GB9224@mail.hallyn.com/ [19]: https://lore.kernel.org/lkml/20181208054059.19813-1-christian@brauner.io/ [20]: https://lore.kernel.org/lkml/8736rebl9s.fsf@oldenburg.str.redhat.com/ [21]: https://lore.kernel.org/lkml/20181228152012.dbf0508c2508138efc5f2bbe@linux-foundation.org/ [22]: https://lore.kernel.org/lkml/20181228233725.722tdfgijxcssg76@brauner.io/ [23]: https://lwn.net/Articles/773459/ [24]: https://lore.kernel.org/lkml/8736rebl9s.fsf@oldenburg.str.redhat.com/ [25]: https://lore.kernel.org/lkml/CAK8P3a0ej9NcJM8wXNPbcGUyOUZYX+VLoDFdbenW3s3114oQZw@mail.gmail.com/ Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Jann Horn <jannh@google.com> Cc: Andy Lutomirsky <luto@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Florian Weimer <fweimer@redhat.com> Signed-off-by: Christian Brauner <christian@brauner.io> Reviewed-by: Tycho Andersen <tycho@tycho.ws> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Howells <dhowells@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Serge Hallyn <serge@hallyn.com> Acked-by: Aleksa Sarai <cyphar@cyphar.com>
* | | Merge tag 'nfs-for-5.1-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfsLinus Torvalds2019-03-161-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull NFS client bugfixes from Trond Myklebust: "Highlights include: Bugfixes: - Fix an Oops in SUNRPC back channel tracepoints - Fix a SUNRPC client regression when handling oversized replies - Fix the minimal size for SUNRPC reply buffer allocation - rpc_decode_header() must always return a non-zero value on error - Fix a typo in pnfs_update_layout() Cleanup: - Remove redundant check for the reply length in call_decode()" * tag 'nfs-for-5.1-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: SUNRPC: Remove redundant check for the reply length in call_decode() SUNRPC: Handle the SYSTEM_ERR rpc error SUNRPC: rpc_decode_header() must always return a non-zero value on error SUNRPC: Use the ENOTCONN error on socket disconnect SUNRPC: Fix the minimal size for reply buffer allocation SUNRPC: Fix a client regression when handling oversized replies pNFS: Fix a typo in pnfs_update_layout fix null pointer deref in tracepoints in back channel
| * | | pNFS: Fix a typo in pnfs_update_layoutTrond Myklebust2019-03-121-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We're supposed to wait for the outstanding layout count to go to zero, but that got lost somehow. Fixes: d03360aaf5cca ("pNFS: Ensure we return the error if someone...") Reported-by: Anna Schumaker <Anna.Schumaker@Netapp.com> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
* | | | Merge branch 'work.mount' of ↵Linus Torvalds2019-03-161-3/+5
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs mount infrastructure fix from Al Viro: "Fixup for sysfs braino. Capabilities checks for sysfs mount do include those on netns, but only if CONFIG_NET_NS is enabled. Sorry, should've caught that earlier..." * 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fix sysfs_init_fs_context() in !CONFIG_NET_NS case
| * | | | fix sysfs_init_fs_context() in !CONFIG_NET_NS caseAl Viro2019-03-161-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Permission checks on current's netns should be done only when netns are enabled. Reported-by: Dominik Brodowski <linux@dominikbrodowski.net> Fixes: 23bf1b6be9c2 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | Merge tag '5.1-rc-smb3' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds2019-03-1615-349/+957
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more smb3 updates from Steve French: "Various tracing and debugging improvements, crediting fixes, some cleanup, and important fallocate fix (fixes three xfstests) and lock fix. Summary: - Various additional dynamic tracing tracepoints - Debugging improvements (including ability to query the server via SMB3 fsctl from userspace tools which can help with stats and debugging) - One minor performance improvement (root directory inode caching) - Crediting (SMB3 flow control) fixes - Some cleanup (docs and to mknod) - Important fixes: one to smb3 implementation of fallocate zero range (which fixes three xfstests) and a POSIX lock fix" * tag '5.1-rc-smb3' of git://git.samba.org/sfrench/cifs-2.6: (22 commits) CIFS: fix POSIX lock leak and invalid ptr deref SMB3: Allow SMB3 FSCTL queries to be sent to server from tools cifs: fix incorrect handling of smb2_set_sparse() return in smb3_simple_falloc smb2: fix typo in definition of a few error flags CIFS: make mknod() an smb_version_op cifs: minor documentation updates cifs: remove unused value pointed out by Coverity SMB3: passthru query info doesn't check for SMB3 FSCTL passthru smb3: add dynamic tracepoints for simple fallocate and zero range cifs: fix smb3_zero_range so it can expand the file-size when required cifs: add SMB2_ioctl_init/free helpers to be used with compounding smb3: Add dynamic trace points for various compounded smb3 ops cifs: cache FILE_ALL_INFO for the shared root handle smb3: display volume serial number for shares in /proc/fs/cifs/DebugData cifs: simplify how we handle credits in compound_send_recv() smb3: add dynamic tracepoint for timeout waiting for credits smb3: display security information in /proc/fs/cifs/DebugData more accurately cifs: add a timeout argument to wait_for_free_credits cifs: prevent starvation in wait_for_free_credits for multi-credit requests cifs: wait_for_free_credits() make it possible to wait for >=1 credits ...
| * | | | | CIFS: fix POSIX lock leak and invalid ptr derefAurelien Aptel2019-03-151-1/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have a customer reporting crashes in lock_get_status() with many "Leaked POSIX lock" messages preceeding the crash. Leaked POSIX lock on dev=0x0:0x56 ... Leaked POSIX lock on dev=0x0:0x56 ... Leaked POSIX lock on dev=0x0:0x56 ... Leaked POSIX lock on dev=0x0:0x53 ... Leaked POSIX lock on dev=0x0:0x53 ... Leaked POSIX lock on dev=0x0:0x53 ... Leaked POSIX lock on dev=0x0:0x53 ... POSIX: fl_owner=ffff8900e7b79380 fl_flags=0x1 fl_type=0x1 fl_pid=20709 Leaked POSIX lock on dev=0x0:0x4b ino... Leaked locks on dev=0x0:0x4b ino=0xf911400000029: POSIX: fl_owner=ffff89f41c870e00 fl_flags=0x1 fl_type=0x1 fl_pid=19592 stack segment: 0000 [#1] SMP Modules linked in: binfmt_misc msr tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag rpcsec_gss_krb5 arc4 ecb auth_rpcgss nfsv4 md4 nfs nls_utf8 lockd grace cifs sunrpc ccm dns_resolver fscache af_packet iscsi_ibft iscsi_boot_sysfs vmw_vsock_vmci_transport vsock xfs libcrc32c sb_edac edac_core crct10dif_pclmul crc32_pclmul ghash_clmulni_intel drbg ansi_cprng vmw_balloon aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd joydev pcspkr vmxnet3 i2c_piix4 vmw_vmci shpchp fjes processor button ac btrfs xor raid6_pq sr_mod cdrom ata_generic sd_mod ata_piix vmwgfx crc32c_intel drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm serio_raw ahci libahci drm libata vmw_pvscsi sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4 Supported: Yes CPU: 6 PID: 28250 Comm: lsof Not tainted 4.4.156-94.64-default #1 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 04/05/2016 task: ffff88a345f28740 ti: ffff88c74005c000 task.ti: ffff88c74005c000 RIP: 0010:[<ffffffff8125dcab>] [<ffffffff8125dcab>] lock_get_status+0x9b/0x3b0 RSP: 0018:ffff88c74005fd90 EFLAGS: 00010202 RAX: ffff89bde83e20ae RBX: ffff89e870003d18 RCX: 0000000049534f50 RDX: ffffffff81a3541f RSI: ffffffff81a3544e RDI: ffff89bde83e20ae RBP: 0026252423222120 R08: 0000000020584953 R09: 000000000000ffff R10: 0000000000000000 R11: ffff88c74005fc70 R12: ffff89e5ca7b1340 R13: 00000000000050e5 R14: ffff89e870003d30 R15: ffff89e5ca7b1340 FS: 00007fafd64be800(0000) GS:ffff89f41fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001c80018 CR3: 000000a522048000 CR4: 0000000000360670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: 0000000000000208 ffffffff81a3d6b6 ffff89e870003d30 ffff89e870003d18 ffff89e5ca7b1340 ffff89f41738d7c0 ffff89e870003d30 ffff89e5ca7b1340 ffffffff8125e08f 0000000000000000 ffff89bc22b67d00 ffff88c74005ff28 Call Trace: [<ffffffff8125e08f>] locks_show+0x2f/0x70 [<ffffffff81230ad1>] seq_read+0x251/0x3a0 [<ffffffff81275bbc>] proc_reg_read+0x3c/0x70 [<ffffffff8120e456>] __vfs_read+0x26/0x140 [<ffffffff8120e9da>] vfs_read+0x7a/0x120 [<ffffffff8120faf2>] SyS_read+0x42/0xa0 [<ffffffff8161cbc3>] entry_SYSCALL_64_fastpath+0x1e/0xb7 When Linux closes a FD (close(), close-on-exec, dup2(), ...) it calls filp_close() which also removes all posix locks. The lock struct is initialized like so in filp_close() and passed down to cifs ... lock.fl_type = F_UNLCK; lock.fl_flags = FL_POSIX | FL_CLOSE; lock.fl_start = 0; lock.fl_end = OFFSET_MAX; ... Note the FL_CLOSE flag, which hints the VFS code that this unlocking is done for closing the fd. filp_close() locks_remove_posix(filp, id); vfs_lock_file(filp, F_SETLK, &lock, NULL); return filp->f_op->lock(filp, cmd, fl) => cifs_lock() rc = cifs_setlk(file, flock, type, wait_flag, posix_lck, lock, unlock, xid); rc = server->ops->mand_unlock_range(cfile, flock, xid); if (flock->fl_flags & FL_POSIX && !rc) rc = locks_lock_file_wait(file, flock) Notice how we don't call locks_lock_file_wait() which does the generic VFS lock/unlock/wait work on the inode if rc != 0. If we are closing the handle, the SMB server is supposed to remove any locks associated with it. Similarly, cifs.ko frees and wakes up any lock and lock waiter when closing the file: cifs_close() cifsFileInfo_put(file->private_data) /* * Delete any outstanding lock records. We'll lose them when the file * is closed anyway. */ down_write(&cifsi->lock_sem); list_for_each_entry_safe(li, tmp, &cifs_file->llist->locks, llist) { list_del(&li->llist); cifs_del_lock_waiters(li); kfree(li); } list_del(&cifs_file->llist->llist); kfree(cifs_file->llist); up_write(&cifsi->lock_sem); So we can safely ignore unlocking failures in cifs_lock() if they happen with the FL_CLOSE flag hint set as both the server and the client take care of it during the actual closing. This is not a proper fix for the unlocking failure but it's safe and it seems to prevent the lock leakages and crashes the customer experiences. Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: NeilBrown <neil@brown.name> Signed-off-by: Steve French <stfrench@microsoft.com> Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | SMB3: Allow SMB3 FSCTL queries to be sent to server from toolsRonnie Sahlberg2019-03-151-16/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For debugging purposes we often have to be able to query additional information only available via SMB3 FSCTL from the server from user space tools (e.g. like cifs-utils's smbinfo). See MS-FSCC and MS-SMB2 protocol specifications for more details. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | | cifs: fix incorrect handling of smb2_set_sparse() return in smb3_simple_fallocRonnie Sahlberg2019-03-151-2/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | smb2_set_sparse does not return -errno, it returns a boolean where true means success. Change this to just ignore the return value just like the other callsites. Additionally add code to handle the case where we must set the file sparse and possibly also extending it. Fixes xfstests: generic/236 generic/350 generic/420 Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | | smb2: fix typo in definition of a few error flagsSteve French2019-03-151-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Sergey Senozhatsky pointed out __constant_cpu_to_le32() is misspelled in a few definitions in the list of status codes smb2status.h as __constanst_cpu_to_le32() Signed-off-by: Steve French <stfrench@microsoft.com> CC: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
| * | | | | CIFS: make mknod() an smb_version_opAurelien Aptel2019-03-154-104/+239
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This cleanup removes cifs specific code from SMB2/SMB3 code paths which is cleaner and easier to maintain as the code to handle special files is improved. Below is an example creating special files using 'sfu' mount option over SMB3 to Windows (with this patch) (Note that to Samba server, support for saving dos attributes has to be enabled for the SFU mount option to work). In the future this will also make implementation of creating special files as reparse points easier (as Windows NFS server does for example). root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/char character special file root@smf-Thinkpad-P51:~# stat -c "%F" /mnt2/block block special file Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
| * | | | | cifs: minor documentation updatesSteve French2019-03-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also updated a comment describing use of the GlobalMid_Lock Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | | cifs: remove unused value pointed out by CoveritySteve French2019-03-151-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Detected by CoverityScan CID#1438719 ("Unused Value") buf is reset again before being used so these two lines of code are useless. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
| * | | | | SMB3: passthru query info doesn't check for SMB3 FSCTL passthruSteve French2019-03-152-7/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The passthrough queries from user space tools like smbinfo can be either SMB3 QUERY_INFO or SMB3 FSCTL, but we are not checking for the latter. Temporarily we return EOPNOTSUPP for SMB3 FSCTL passthrough requests but once compounding fsctls is fixed can enable. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
| * | | | | smb3: add dynamic tracepoints for simple fallocate and zero rangeSteve French2019-03-152-0/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Can be helpful in debugging various xfstests that are currently skipped or failing due to missing features in our current implementation of fallocate. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
| * | | | | cifs: fix smb3_zero_range so it can expand the file-size when requiredRonnie Sahlberg2019-03-153-19/+68
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This allows fallocate -z to work against a Windows2016 share. This is due to the SMB3 ZERO_RANGE command does not modify the filesize. To address this we will now append a compounded SET-INFO to update the end-of-file information. This brings xfstests generic/469 closer to working against a windows share. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | | cifs: add SMB2_ioctl_init/free helpers to be used with compoundingRonnie Sahlberg2019-03-152-57/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Define an _init() and a _free() function for SMB2_init so that we will be able to use it with compounds. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | | smb3: Add dynamic trace points for various compounded smb3 opsSteve French2019-03-152-4/+185
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Adds trace points for enter and exit (done vs. error) for: compounded query and setinfo, hardlink, rename, mkdir, rmdir, set_eof, delete (unlink) Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
| * | | | | cifs: cache FILE_ALL_INFO for the shared root handleRonnie Sahlberg2019-03-155-28/+118
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we open the shared root handle also ask for FILE_ALL_INFORMATION since we can do this at zero cost as part of a compound. Cache this information as long as the lease is held and return and serve any future requests from cache. This allows us to serve "stat /<mountpoint>" directly from cache and avoid a network roundtrip. Since clients often want to do this quite a lot this improve performance slightly. As an example: xfstest generic/533 performs 43 stat operations on the root of the share while it is run. Which are eliminated with this patch. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | smb3: display volume serial number for shares in /proc/fs/cifs/DebugDataSteve French2019-03-151-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It can be helpful for debugging. According to MS-FSCC: "A 32-bit unsigned integer that contains the serial number of the volume. The serial number is an opaque value generated by the file system at format time" Signed-off-by: Steve French <stfrench@microsoft.com> Acked-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | cifs: simplify how we handle credits in compound_send_recv()Ronnie Sahlberg2019-03-151-72/+38
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since we can now wait for multiple requests atomically in wait_for_free_request() we can now greatly simplify the handling of the credits in this function. This fixes a potential deadlock where many concurrent compound requests could each have reserved 1 or 2 credits each but are all blocked waiting for the final credits they need to be able to issue the requests to the server. Set a default timeout of 60 seconds for compounded requests. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | smb3: add dynamic tracepoint for timeout waiting for creditsSteve French2019-03-152-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To help debug credit starvation problems where we timeout waiting for server to grant the client credits. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | smb3: display security information in /proc/fs/cifs/DebugData more accuratelySteve French2019-03-151-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the server required encryption (but we didn't connect to it with the "seal" mount option) we weren't displaying in /proc/fs/cifs/DebugData that the tcon for that share was encrypted. Similarly we were not displaying that signing was required when ses->sign was enabled (we only checked ses->server->sign). This makes it easier to debug when in fact the connection is signed (or sealed), whether for performance or security questions. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
| * | | | | cifs: add a timeout argument to wait_for_free_creditsRonnie Sahlberg2019-03-151-10/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A negative timeout is the same as the current behaviour, i.e. no timeout. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | cifs: prevent starvation in wait_for_free_credits for multi-credit requestsRonnie Sahlberg2019-03-151-0/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reserve the last MAX_COMPOUND credits for any request asking for >1 credit. This is to prevent future compound requests from becoming starved while waiting for potentially many requests is there is a large number of concurrent singe-credit requests. However, we need to protect from servers that are very slow to hand out new credits on new sessions so we only do this IFF there are 2*MAX_COMPOUND (arbitrary) credits already in flight. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | cifs: wait_for_free_credits() make it possible to wait for >=1 creditsRonnie Sahlberg2019-03-153-10/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change wait_for_free_credits() to allow waiting for >=1 credits instead of just a single credit. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | cifs: pass flags down into wait_for_free_credits()Ronnie Sahlberg2019-03-151-16/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | | cifs: change wait_for_free_request() to take flags as argumentRonnie Sahlberg2019-03-151-16/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | and compute timeout and optyp from it. Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
* | | | | | Merge tag 'xfs-5.1-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2019-03-152-30/+25
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull xfs cleanups from Darrick Wong: "Here's a few more cleanups that trickled in for the merge window. It's all fixes for static checker complaints and slowly unwinding typedef usage. The four patches here have gone through a few days worth of fstest runs with no new problems observed. Summary: - Fix some clang/smatch/sparse warnings about uninitialized variables. - Clean up some typedef usage" * tag 'xfs-5.1-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: clean up xfs_dir2_leaf_addname xfs: zero initialize highstale and lowstale in xfs_dir2_leaf_addname xfs: clean up xfs_dir2_leafn_add xfs: Zero initialize highstale and lowstale in xfs_dir2_leafn_add
| * | | | | | xfs: clean up xfs_dir2_leaf_addnameDarrick J. Wong2019-03-121-18/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove typedefs and consolidate local variable initialization. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Bill O'Donnell <billodo@redhat.com>
| * | | | | | xfs: zero initialize highstale and lowstale in xfs_dir2_leaf_addnameDarrick J. Wong2019-03-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Smatch complains about the following: fs/xfs/libxfs/xfs_dir2_leaf.c:848 xfs_dir2_leaf_addname() error: uninitialized symbol 'lowstale'. fs/xfs/libxfs/xfs_dir2_leaf.c:849 xfs_dir2_leaf_addname() error: uninitialized symbol 'highstale'. I don't think there's any incorrect behavior associated with the uninitialized variable, but as the author of the previous zero-init patch points out, it's best not to be passing around pointers to uninitialized stack areas. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Reviewed-by: Bill O'Donnell <billodo@redhat.com>
| * | | | | | xfs: clean up xfs_dir2_leafn_addDarrick J. Wong2019-03-081-12/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Remove typedefs and consolidate local variable initialization. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
| * | | | | | xfs: Zero initialize highstale and lowstale in xfs_dir2_leafn_addNathan Chancellor2019-03-081-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When building with -Wsometimes-uninitialized, Clang warns: fs/xfs/libxfs/xfs_dir2_node.c:481:6: warning: variable 'lowstale' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] fs/xfs/libxfs/xfs_dir2_node.c:481:6: warning: variable 'highstale' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] While it isn't technically wrong, it isn't a problem in practice because highstale and lowstale are only initialized in xfs_dir2_leafn_add when compact is not zero then they are passed to xfs_dir3_leaf_find_entry, where they are initialized before use when compact is zero. Regardless, it's better not to be passing around uninitialized stack memory so zero initialize these variables, which silences this warning. Link: https://github.com/ClangBuiltLinux/linux/issues/393 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
* | | | | | | Merge tag 'f2fs-for-5.1' of ↵Linus Torvalds2019-03-1518-175/+358
|\ \ \ \ \ \ \ | |_|/ / / / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "We've continued mainly to fix bugs in this round, as f2fs has been shipped in more devices. Especially, we've focused on stabilizing checkpoint=disable feature, and provided some interfaces for QA. Enhancements: - expose FS_NOCOW_FL for pin_file - run discard jobs at unmount time with timeout - tune discarding thread to avoid idling which consumes power - some checking codes to address vulnerabilities - give random value to i_generation - shutdown with more flags for QA Bug fixes: - clean up stale objects when mount is failed along with checkpoint=disable - fix system being stuck due to wrong count by atomic writes - handle some corrupted disk cases - fix a deadlock in f2fs_read_inline_dir We've also added some minor build error fixes and clean-up patches" * tag 'f2fs-for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (53 commits) f2fs: set pin_file under CAP_SYS_ADMIN f2fs: fix to avoid deadlock in f2fs_read_inline_dir() f2fs: fix to adapt small inline xattr space in __find_inline_xattr() f2fs: fix to do sanity check with inode.i_inline_xattr_size f2fs: give some messages for inline_xattr_size f2fs: don't trigger read IO for beyond EOF page f2fs: fix to add refcount once page is tagged PG_private f2fs: remove wrong comment in f2fs_invalidate_page() f2fs: fix to use kvfree instead of kzfree f2fs: print more parameters in trace_f2fs_map_blocks f2fs: trace f2fs_ioc_shutdown f2fs: fix to avoid deadlock of atomic file operations f2fs: fix to dirty inode for i_mode recovery f2fs: give random value to i_generation f2fs: no need to take page lock in readdir f2fs: fix to update iostat correctly in IPU path f2fs: fix encrypted page memory leak f2fs: make fault injection covering __submit_flush_wait() f2fs: fix to retry fill_super only if recovery failed f2fs: silence VM_WARN_ON_ONCE in mempool_alloc ...
| * | | | | | f2fs: set pin_file under CAP_SYS_ADMINJaegeuk Kim2019-03-141-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Android uses pin_file for uncrypt during OTA, and that should be managed by CAP_SYS_ADMIN only. Reviewed-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: fix to avoid deadlock in f2fs_read_inline_dir()Chao Yu2019-03-131-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Jiqun Li reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202883 sometimes, dead lock when make system call SYS_getdents64 with fsync() is called by another process. monkey running on android9.0 1. task 9785 held sbi->cp_rwsem and waiting lock_page() 2. task 10349 held mm_sem and waiting sbi->cp_rwsem 3. task 9709 held lock_page() and waiting mm_sem so this is a dead lock scenario. task stack is show by crash tools as following crash_arm64> bt ffffffc03c354080 PID: 9785 TASK: ffffffc03c354080 CPU: 1 COMMAND: "RxIoScheduler-3" >> #7 [ffffffc01b50fac0] __lock_page at ffffff80081b11e8 crash-arm64> bt 10349 PID: 10349 TASK: ffffffc018b83080 CPU: 1 COMMAND: "BUGLY_ASYNC_UPL" >> #3 [ffffffc01f8cfa40] rwsem_down_read_failed at ffffff8008a93afc PC: 00000033 LR: 00000000 SP: 00000000 PSTATE: ffffffffffffffff crash-arm64> bt 9709 PID: 9709 TASK: ffffffc03e7f3080 CPU: 1 COMMAND: "IntentService[A" >> #3 [ffffffc001e67850] rwsem_down_read_failed at ffffff8008a93afc >> #8 [ffffffc001e67b80] el1_ia at ffffff8008084fc4 PC: ffffff8008274114 [compat_filldir64+120] LR: ffffff80083584d4 [f2fs_fill_dentries+448] SP: ffffffc001e67b80 PSTATE: 80400145 X29: ffffffc001e67b80 X28: 0000000000000000 X27: 000000000000001a X26: 00000000000093d7 X25: ffffffc070d52480 X24: 0000000000000008 X23: 0000000000000028 X22: 00000000d43dfd60 X21: ffffffc001e67e90 X20: 0000000000000011 X19: ffffff80093a4000 X18: 0000000000000000 X17: 0000000000000000 X16: 0000000000000000 X15: 0000000000000000 X14: ffffffffffffffff X13: 0000000000000008 X12: 0101010101010101 X11: 7f7f7f7f7f7f7f7f X10: 6a6a6a6a6a6a6a6a X9: 7f7f7f7f7f7f7f7f X8: 0000000080808000 X7: ffffff800827409c X6: 0000000080808000 X5: 0000000000000008 X4: 00000000000093d7 X3: 000000000000001a X2: 0000000000000011 X1: ffffffc070d52480 X0: 0000000000800238 >> #9 [ffffffc001e67be0] f2fs_fill_dentries at ffffff80083584d0 PC: 0000003c LR: 00000000 SP: 00000000 PSTATE: 000000d9 X12: f48a02ff X11: d4678960 X10: d43dfc00 X9: d4678ae4 X8: 00000058 X7: d4678994 X6: d43de800 X5: 000000d9 X4: d43dfc0c X3: d43dfc10 X2: d46799c8 X1: 00000000 X0: 00001068 Below potential deadlock will happen between three threads: Thread A Thread B Thread C - f2fs_do_sync_file - f2fs_write_checkpoint - down_write(&sbi->node_change) -- 1) - do_page_fault - down_write(&mm->mmap_sem) -- 2) - do_wp_page - f2fs_vm_page_mkwrite - getdents64 - f2fs_read_inline_dir - lock_page -- 3) - f2fs_sync_node_pages - lock_page -- 3) - __do_map_lock - down_read(&sbi->node_change) -- 1) - f2fs_fill_dentries - dir_emit - compat_filldir64 - do_page_fault - down_read(&mm->mmap_sem) -- 2) Since f2fs_readdir is protected by inode.i_rwsem, there should not be any updates in inode page, we're safe to lookup dents in inode page without its lock held, so taking off the lock to improve concurrency of readdir and avoid potential deadlock. Reported-by: Jiqun Li <jiqun.li@unisoc.com> Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: fix to adapt small inline xattr space in __find_inline_xattr()Chao Yu2019-03-131-3/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With below testcase, we will fail to find existed xattr entry: 1. mkfs.f2fs -O extra_attr -O flexible_inline_xattr /dev/zram0 2. mount -t f2fs -o inline_xattr_size=1 /dev/zram0 /mnt/f2fs/ 3. touch /mnt/f2fs/file 4. setfattr -n "user.name" -v 0 /mnt/f2fs/file 5. getfattr -n "user.name" /mnt/f2fs/file /mnt/f2fs/file: user.name: No such attribute The reason is for inode which has very small inline xattr size, __find_inline_xattr() will fail to traverse any entry due to first entry may not be loaded from xattr node yet, later, we may skip to check entire xattr datas in __find_xattr(), result in such wrong condition. This patch adds condition to check such case to avoid this issue. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: fix to do sanity check with inode.i_inline_xattr_sizeChao Yu2019-03-133-4/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Paul Bandha reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202709 When I run the poc on the mounted f2fs img I get a buffer overflow in read_inline_xattr due to there being no sanity check on the value of i_inline_xattr_size. I created the img by just modifying the value of i_inline_xattr_size in the inode: i_name [test1.txt] i_ext: fofs:0 blkaddr:0 len:0 i_extra_isize [0x 18 : 24] i_inline_xattr_size [0x ffff : 65535] i_addr[ofs] [0x 0 : 0] mkdir /mnt/f2fs mount ./f2fs1.img /mnt/f2fs gcc poc.c -o poc ./poc int main() { int y = syscall(SYS_listxattr, "/mnt/f2fs/test1.txt", NULL, 0); printf("ret %d", y); printf("errno: %d\n", errno); } BUG: KASAN: slab-out-of-bounds in read_inline_xattr+0x18f/0x260 Read of size 262140 at addr ffff88011035efd8 by task f2fs1poc/3263 CPU: 0 PID: 3263 Comm: f2fs1poc Not tainted 4.18.0-custom #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014 Call Trace: dump_stack+0x71/0xab print_address_description+0x83/0x250 kasan_report+0x213/0x350 memcpy+0x1f/0x50 read_inline_xattr+0x18f/0x260 read_all_xattrs+0xba/0x190 f2fs_listxattr+0x9d/0x3f0 listxattr+0xb2/0xd0 path_listxattr+0x93/0xe0 do_syscall_64+0x9d/0x220 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Let's add sanity check for inode.i_inline_xattr_size during f2fs_iget() to avoid this issue. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: give some messages for inline_xattr_sizeJaegeuk Kim2019-03-131-6/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds some kernel messages when user sets wrong inline_xattr_size. Fixes: 500e0b28ecd3 ("f2fs: fix to check inline_xattr_size boundary correctly") Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: don't trigger read IO for beyond EOF pageChao Yu2019-03-131-9/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In f2fs_mpage_readpages(), if page is beyond EOF, we should just zero out it, but previously, before checking previous mapping info, we missed to check filesize boundary, fix it. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: fix to add refcount once page is tagged PG_privateChao Yu2019-03-136-23/+36
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Gao Xiang reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202749 f2fs may skip pageout() due to incorrect page reference count. The problem here is that MM defined the rule [1] very clearly that once page was set with PG_private flag, we should increment the refcount in that page, also main flows like pageout(), migrate_page() will assume there is one additional page reference count if page_has_private() returns true. But currently, f2fs won't add/del refcount when changing PG_private flag. Anyway, f2fs should follow MM's rule to make MM's related flows running as expected. [1] https://lore.kernel.org/lkml/2b19b3c4-2bc4-15fa-15cc-27a13e5c7af1@aol.com/ Reported-by: Gao Xiang <gaoxiang25@huawei.com> Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: remove wrong comment in f2fs_invalidate_page()Chao Yu2019-03-131-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since 8c242db9b8c0 ("f2fs: fix stale ATOMIC_WRITTEN_PAGE private pointer"), we've started to not skip clear private flag for atomic_write page truncation, so removing old wrong comment in f2fs_invalidate_page(). Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: fix to use kvfree instead of kzfreeChao Yu2019-03-131-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Jiqun Li reported in bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202747 System can panic due to using wrong allocate/free function pair in xattr interface: - use kvmalloc to allocate memory - use kzfree to free memory Let's fix to use kvfree instead of kzfree, BTW, we are safe to get rid of kzfree, since there is no such confidential data stored as xattr, we don't need to zero it before free memory. Fixes: 5222595d093e ("f2fs: use kvmalloc, if kmalloc is failed") Reported-by: Jiqun Li <jiqun.li@unisoc.com> Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: trace f2fs_ioc_shutdownChao Yu2019-03-131-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch supports to trace f2fs_ioc_shutdown. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| * | | | | | f2fs: fix to avoid deadlock of atomic file operationsChao Yu2019-03-131-12/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Thread A Thread B - __fput - f2fs_release_file - drop_inmem_pages - mutex_lock(&fi->inmem_lock) - __revoke_inmem_pages - lock_page(page) - open - f2fs_setattr - truncate_setsize - truncate_inode_pages_range - lock_page(page) - truncate_cleanup_page - f2fs_invalidate_page - drop_inmem_page - mutex_lock(&fi->inmem_lock); We may encounter above ABBA deadlock as reported by Kyungtae Kim: I'm reporting a bug in linux-4.17.19: "INFO: task hung in drop_inmem_page" (no reproducer) I think this might be somehow related to the following: https://groups.google.com/forum/#!searchin/syzkaller-bugs/INFO$3A$20task$20hung$20in$20%7Csort:date/syzkaller-bugs/c6soBTrdaIo/AjAzPeIzCgAJ ========================================= INFO: task syz-executor7:10822 blocked for more than 120 seconds. Not tainted 4.17.19 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor7 D27024 10822 6346 0x00000004 Call Trace: context_switch kernel/sched/core.c:2867 [inline] __schedule+0x721/0x1e60 kernel/sched/core.c:3515 schedule+0x88/0x1c0 kernel/sched/core.c:3559 schedule_preempt_disabled+0x18/0x30 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x5bd/0x1410 kernel/locking/mutex.c:893 mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:908 drop_inmem_page+0xcb/0x810 fs/f2fs/segment.c:327 f2fs_invalidate_page+0x337/0x5e0 fs/f2fs/data.c:2401 do_invalidatepage mm/truncate.c:165 [inline] truncate_cleanup_page+0x261/0x330 mm/truncate.c:187 truncate_inode_pages_range+0x552/0x1610 mm/truncate.c:367 truncate_inode_pages mm/truncate.c:478 [inline] truncate_pagecache+0x6d/0x90 mm/truncate.c:801 truncate_setsize+0x81/0xa0 mm/truncate.c:826 f2fs_setattr+0x44f/0x1270 fs/f2fs/file.c:781 notify_change+0xa62/0xe80 fs/attr.c:313 do_truncate+0x12e/0x1e0 fs/open.c:63 do_last fs/namei.c:2955 [inline] path_openat+0x2042/0x29f0 fs/namei.c:3505 do_filp_open+0x1bd/0x2c0 fs/namei.c:3540 do_sys_open+0x35e/0x4e0 fs/open.c:1101 __do_sys_open fs/open.c:1119 [inline] __se_sys_open fs/open.c:1114 [inline] __x64_sys_open+0x89/0xc0 fs/open.c:1114 do_syscall_64+0xc4/0x4e0 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4497b9 RSP: 002b:00007f734e459c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f734e45a6cc RCX: 00000000004497b9 RDX: 0000000000000104 RSI: 00000000000a8280 RDI: 0000000020000080 RBP: 000000000071bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000007230 R14: 00000000006f02d0 R15: 00007f734e45a700 INFO: task syz-executor7:10858 blocked for more than 120 seconds. Not tainted 4.17.19 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor7 D28880 10858 6346 0x00000004 Call Trace: context_switch kernel/sched/core.c:2867 [inline] __schedule+0x721/0x1e60 kernel/sched/core.c:3515 schedule+0x88/0x1c0 kernel/sched/core.c:3559 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:565 [inline] rwsem_down_write_failed+0x5e6/0xc90 kernel/locking/rwsem-xadd.c:594 call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117 __down_write arch/x86/include/asm/rwsem.h:142 [inline] down_write+0x58/0xa0 kernel/locking/rwsem.c:72 inode_lock include/linux/fs.h:713 [inline] do_truncate+0x120/0x1e0 fs/open.c:61 do_last fs/namei.c:2955 [inline] path_openat+0x2042/0x29f0 fs/namei.c:3505 do_filp_open+0x1bd/0x2c0 fs/namei.c:3540 do_sys_open+0x35e/0x4e0 fs/open.c:1101 __do_sys_open fs/open.c:1119 [inline] __se_sys_open fs/open.c:1114 [inline] __x64_sys_open+0x89/0xc0 fs/open.c:1114 do_syscall_64+0xc4/0x4e0 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4497b9 RSP: 002b:00007f734e3b4c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 00007f734e3b56cc RCX: 00000000004497b9 RDX: 0000000000000104 RSI: 00000000000a8280 RDI: 0000000020000080 RBP: 000000000071c238 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000007230 R14: 00000000006f02d0 R15: 00007f734e3b5700 INFO: task syz-executor5:10829 blocked for more than 120 seconds. Not tainted 4.17.19 #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor5 D28760 10829 6308 0x80000002 Call Trace: context_switch kernel/sched/core.c:2867 [inline] __schedule+0x721/0x1e60 kernel/sched/core.c:3515 schedule+0x88/0x1c0 kernel/sched/core.c:3559 io_schedule+0x21/0x80 kernel/sched/core.c:5179 wait_on_page_bit_common mm/filemap.c:1100 [inline] __lock_page+0x2b5/0x390 mm/filemap.c:1273 lock_page include/linux/pagemap.h:483 [inline] __revoke_inmem_pages+0xb35/0x11c0 fs/f2fs/segment.c:231 drop_inmem_pages+0xa3/0x3e0 fs/f2fs/segment.c:306 f2fs_release_file+0x2c7/0x330 fs/f2fs/file.c:1556 __fput+0x2c7/0x780 fs/file_table.c:209 ____fput+0x1a/0x20 fs/file_table.c:243 task_work_run+0x151/0x1d0 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x8ba/0x30a0 kernel/exit.c:865 do_group_exit+0x13b/0x3a0 kernel/exit.c:968 get_signal+0x6bb/0x1650 kernel/signal.c:2482 do_signal+0x84/0x1b70 arch/x86/kernel/signal.c:810 exit_to_usermode_loop+0x155/0x190 arch/x86/entry/common.c:162 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:265 [inline] do_syscall_64+0x445/0x4e0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4497b9 RSP: 002b:00007f1c68e74ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffe00 RBX: 000000000071bf80 RCX: 00000000004497b9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000071bf80 RBP: 000000000071bf80 R08: 0000000000000000 R09: 000000000071bf58 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f1c68e759c0 R15: 00007f1c68e75700 This patch tries to use trylock_page to mitigate such deadlock condition for fix. Signed-off-by: Chao Yu <yuchao0@huawei.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>