diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2023-04-14 15:46:39 +0200 |
|---|---|---|
| committer | Richard Weinberger <richard@nod.at> | 2023-04-20 23:08:43 +0200 |
| commit | 6032aca0deb9c138df122192f8ef02de1fdccf25 (patch) | |
| tree | f9acfe2a2c09cfa1b3a86351b8bdf2ccd8fa48ef /arch/um/os-Linux | |
| parent | um: prevent user code in modules (diff) | |
| download | linux-6032aca0deb9c138df122192f8ef02de1fdccf25.tar.xz linux-6032aca0deb9c138df122192f8ef02de1fdccf25.zip | |
um: make stub data pages size tweakable
There's a lot of code here that hard-codes that the
data is a single page, and right now that seems to
be sufficient, but to make it easier to change this
in the future, add a new STUB_DATA_PAGES constant
and use it throughout the code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Diffstat (limited to 'arch/um/os-Linux')
| -rw-r--r-- | arch/um/os-Linux/skas/process.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c index b1ea53285af1..9464833e741a 100644 --- a/arch/um/os-Linux/skas/process.c +++ b/arch/um/os-Linux/skas/process.c @@ -262,7 +262,7 @@ static int userspace_tramp(void *stack) if (stack != NULL) { fd = phys_mapping(uml_to_phys(stack), &offset); addr = mmap((void *) STUB_DATA, - UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE, + STUB_DATA_PAGES * UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED, fd, offset); if (addr == MAP_FAILED) { printk(UM_KERN_ERR "mapping segfault stack at 0x%lx failed, errno = %d\n", @@ -277,7 +277,7 @@ static int userspace_tramp(void *stack) (unsigned long) stub_segv_handler - (unsigned long) __syscall_stub_start; - set_sigstack((void *) STUB_DATA, UM_KERN_PAGE_SIZE); + set_sigstack((void *) STUB_DATA, STUB_DATA_PAGES * UM_KERN_PAGE_SIZE); sigemptyset(&sa.sa_mask); sa.sa_flags = SA_ONSTACK | SA_NODEFER | SA_SIGINFO; sa.sa_sigaction = (void *) v; @@ -515,7 +515,7 @@ static int __init init_thread_regs(void) thread_regs[REGS_IP_INDEX] = STUB_CODE + (unsigned long) stub_clone_handler - (unsigned long) __syscall_stub_start; - thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE - + thread_regs[REGS_SP_INDEX] = STUB_DATA + STUB_DATA_PAGES * UM_KERN_PAGE_SIZE - sizeof(void *); #ifdef __SIGNAL_FRAMESIZE thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE; |