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* treewide: Use array_size() in vzalloc()Kees Cook2018-06-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The vzalloc() function has no 2-factor argument form, so multiplication factors need to be wrapped in array_size(). This patch replaces cases of: vzalloc(a * b) with: vzalloc(array_size(a, b)) as well as handling cases of: vzalloc(a * b * c) with: vzalloc(array3_size(a, b, c)) This does, however, attempt to ignore constant size factors like: vzalloc(4 * 1024) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( vzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | vzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( vzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | vzalloc( - sizeof(u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | vzalloc( - sizeof(char) * COUNT + COUNT , ...) | vzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( vzalloc( - sizeof(TYPE) * (COUNT_ID) + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_ID + array_size(COUNT_ID, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT_CONST + array_size(COUNT_CONST, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT_ID) + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_ID + array_size(COUNT_ID, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT_CONST) + array_size(COUNT_CONST, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT_CONST + array_size(COUNT_CONST, sizeof(THING)) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ vzalloc( - SIZE * COUNT + array_size(COUNT, SIZE) , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( vzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | vzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( vzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | vzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( vzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | vzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( vzalloc(C1 * C2 * C3, ...) | vzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants. @@ expression E1, E2; constant C1, C2; @@ ( vzalloc(C1 * C2, ...) | vzalloc( - E1 * E2 + array_size(E1, E2) , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
* kernel/kexec_file.c: allow archs to set purgatory load addressPhilipp Rudo2018-04-141-13/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For s390 new kernels are loaded to fixed addresses in memory before they are booted. With the current code this is a problem as it assumes the kernel will be loaded to an 'arbitrary' address. In particular, kexec_locate_mem_hole searches for a large enough memory region and sets the load address (kexec_bufer->mem) to it. Luckily there is a simple workaround for this problem. By returning 1 in arch_kexec_walk_mem, kexec_locate_mem_hole is turned off. This allows the architecture to set kbuf->mem by hand. While the trick works fine for the kernel it does not for the purgatory as here the architectures don't have access to its kexec_buffer. Give architectures access to the purgatories kexec_buffer by changing kexec_load_purgatory to take a pointer to it. With this change architectures have access to the buffer and can edit it as they need. A nice side effect of this change is that we can get rid of the purgatory_info->purgatory_load_address field. As now the information stored there can directly be accessed from kbuf->mem. Link: http://lkml.kernel.org/r/20180321112751.22196-11-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove mis-use of sh_offset field during purgatory loadPhilipp Rudo2018-04-141-30/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | The current code uses the sh_offset field in purgatory_info->sechdrs to store a pointer to the current load address of the section. Depending whether the section will be loaded or not this is either a pointer into purgatory_info->purgatory_buf or kexec_purgatory. This is not only a violation of the ELF standard but also makes the code very hard to understand as you cannot tell if the memory you are using is read-only or not. Remove this misuse and store the offset of the section in pugaroty_info->purgatory_buf in sh_offset. Link: http://lkml.kernel.org/r/20180321112751.22196-10-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove unneeded variables in kexec_purgatory_setup_sechdrsPhilipp Rudo2018-04-141-22/+12
| | | | | | | | | | | | | | | | | | | | The main loop currently uses quite a lot of variables to update the section headers. Some of them are unnecessary. So clean them up a little. Link: http://lkml.kernel.org/r/20180321112751.22196-9-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove unneeded for-loop in kexec_purgatory_setup_sechdrsPhilipp Rudo2018-04-141-46/+30
| | | | | | | | | | | | | | | | | | | | | | | | To update the entry point there is an extra loop over all section headers although this can be done in the main loop. So move it there and eliminate the extra loop and variable to store the 'entry section index'. Also, in the main loop, move the usual case, i.e. non-bss section, out of the extra if-block. Link: http://lkml.kernel.org/r/20180321112751.22196-8-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: split up __kexec_load_puragoryPhilipp Rudo2018-04-141-97/+103
| | | | | | | | | | | | | | | | | | | | | | | | | When inspecting __kexec_load_purgatory you find that it has two tasks 1) setting up the kexec_buffer for the new kernel and, 2) setting up pi->sechdrs for the final load address. The two tasks are independent of each other. To improve readability split up __kexec_load_purgatory into two functions, one for each task, and call them directly from kexec_load_purgatory. Link: http://lkml.kernel.org/r/20180321112751.22196-7-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: use read-only sections in arch_kexec_apply_relocations*Philipp Rudo2018-04-141-21/+42
| | | | | | | | | | | | | | | | | | | | | | | | | | When the relocations are applied to the purgatory only the section the relocations are applied to is writable. The other sections, i.e. the symtab and .rel/.rela, are in read-only kexec_purgatory. Highlight this by marking the corresponding variables as 'const'. While at it also change the signatures of arch_kexec_apply_relocations* to take section pointers instead of just the index of the relocation section. This removes the second lookup and sanity check of the sections in arch code. Link: http://lkml.kernel.org/r/20180321112751.22196-6-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: search symbols in read-only kexec_purgatoryPhilipp Rudo2018-04-141-16/+22
| | | | | | | | | | | | | | | | | | | | The stripped purgatory does not contain a symtab. So when looking for symbols this is done in read-only kexec_purgatory. Highlight this by marking the corresponding variables as 'const'. Link: http://lkml.kernel.org/r/20180321112751.22196-5-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: make purgatory_info->ehdr constPhilipp Rudo2018-04-141-2/+2
| | | | | | | | | | | | | | | | | | | | | The kexec_purgatory buffer is read-only. Thus all pointers into kexec_purgatory are read-only, too. Point this out by explicitly marking purgatory_info->ehdr as 'const' and update the comments in purgatory_info. Link: http://lkml.kernel.org/r/20180321112751.22196-4-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kernel/kexec_file.c: remove checks in kexec_purgatory_loadPhilipp Rudo2018-04-141-14/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before the purgatory is loaded several checks are done whether the ELF file in kexec_purgatory is valid or not. These checks are incomplete. For example they don't check for the total size of the sections defined in the section header table or if the entry point actually points into the purgatory. On the other hand the purgatory, although an ELF file on its own, is part of the kernel. Thus not trusting the purgatory means not trusting the kernel build itself. So remove all validity checks on the purgatory and just trust the kernel build. Link: http://lkml.kernel.org/r/20180321112751.22196-3-prudo@linux.vnet.ibm.com Signed-off-by: Philipp Rudo <prudo@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: AKASHI Takahiro <takahiro.akashi@linaro.org> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file, x86: move re-factored code to generic sideAKASHI Takahiro2018-04-141-0/+175
| | | | | | | | | | | | | | | | In the previous patches, commonly-used routines, exclude_mem_range() and prepare_elf64_headers(), were carved out. Now place them in kexec common code. A prefix "crash_" is given to each of their names to avoid possible name collisions. Link: http://lkml.kernel.org/r/20180306102303.9063-8-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file,x86,powerpc: factor out kexec_file_ops functionsAKASHI Takahiro2018-04-141-4/+56
| | | | | | | | | | | | | | | | | | As arch_kexec_kernel_image_{probe,load}(), arch_kimage_file_post_load_cleanup() and arch_kexec_kernel_verify_sig() are almost duplicated among architectures, they can be commonalized with an architecture-defined kexec_file_ops array. So let's factor them out. Link: http://lkml.kernel.org/r/20180306102303.9063-3-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file: make use of purgatory optionalAKASHI Takahiro2018-04-141-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch series "kexec_file, x86, powerpc: refactoring for other architecutres", v2. This is a preparatory patchset for adding kexec_file support on arm64. It was originally included in a arm64 patch set[1], but Philipp is also working on their kexec_file support on s390[2] and some changes are now conflicting. So these common parts were extracted and put into a separate patch set for better integration. What's more, my original patch#4 was split into a few small chunks for easier review after Dave's comment. As such, the resulting code is basically identical with my original, and the only *visible* differences are: - renaming of _kexec_kernel_image_probe() and _kimage_file_post_load_cleanup() - change one of types of arguments at prepare_elf64_headers() Those, unfortunately, require a couple of trivial changes on the rest (#1, #6 to #13) of my arm64 kexec_file patch set[1]. Patch #1 allows making a use of purgatory optional, particularly useful for arm64. Patch #2 commonalizes arch_kexec_kernel_{image_probe, image_load, verify_sig}() and arch_kimage_file_post_load_cleanup() across architectures. Patches #3-#7 are also intended to generalize parse_elf64_headers(), along with exclude_mem_range(), to be made best re-use of. [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2018-February/561182.html [2] http://lkml.iu.edu//hypermail/linux/kernel/1802.1/02596.html This patch (of 7): On arm64, crash dump kernel's usable memory is protected by *unmapping* it from kernel virtual space unlike other architectures where the region is just made read-only. It is highly unlikely that the region is accidentally corrupted and this observation rationalizes that digest check code can also be dropped from purgatory. The resulting code is so simple as it doesn't require a bit ugly re-linking/relocation stuff, i.e. arch_kexec_apply_relocations_add(). Please see: http://lists.infradead.org/pipermail/linux-arm-kernel/2017-December/545428.html All that the purgatory does is to shuffle arguments and jump into a new kernel, while we still need to have some space for a hash value (purgatory_sha256_digest) which is never checked against. As such, it doesn't make sense to have trampline code between old kernel and new kernel on arm64. This patch introduces a new configuration, ARCH_HAS_KEXEC_PURGATORY, and allows related code to be compiled in only if necessary. [takahiro.akashi@linaro.org: fix trivial screwup] Link: http://lkml.kernel.org/r/20180309093346.GF25863@linaro.org Link: http://lkml.kernel.org/r/20180306102303.9063-2-takahiro.akashi@linaro.org Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org> Acked-by: Dave Young <dyoung@redhat.com> Tested-by: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* resource: Provide resource struct in resource walk callbackTom Lendacky2017-11-071-2/+3
| | | | | | | | | | | | | | | | | | | | | In preperation for a new function that will need additional resource information during the resource walk, update the resource walk callback to pass the resource structure. Since the current callback start and end arguments are pulled from the resource structure, the callback functions can obtain them from the resource structure directly. Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Borislav Petkov <bp@suse.de> Tested-by: Borislav Petkov <bp@suse.de> Cc: kvm@vger.kernel.org Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Borislav Petkov <bp@alien8.de> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lkml.kernel.org/r/20171020143059.3291-10-brijesh.singh@amd.com
* kexec_file: adjust declaration of kexec_purgatoryKees Cook2017-07-131-7/+0
| | | | | | | | | | | | | | | | | Defining kexec_purgatory as a zero-length char array upsets compile time size checking. Since this is built on a per-arch basis, define it as an unsized char array (like is done for other similar things, e.g. linker sections). This silences the warning generated by the future CONFIG_FORTIFY_SOURCE, which did not like the memcmp() of a "0 byte" array. This drops the __weak and uses an extern instead, since both users define kexec_purgatory. Link: http://lkml.kernel.org/r/1497903987-21002-4-git-send-email-keescook@chromium.org Signed-off-by: Kees Cook <keescook@chromium.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Daniel Micay <danielmicay@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kdump: protect vmcoreinfo data under the crash memoryXunlei Pang2017-07-131-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently vmcoreinfo data is updated at boot time subsys_initcall(), it has the risk of being modified by some wrong code during system is running. As a result, vmcore dumped may contain the wrong vmcoreinfo. Later on, when using "crash", "makedumpfile", etc utility to parse this vmcore, we probably will get "Segmentation fault" or other unexpected errors. E.g. 1) wrong code overwrites vmcoreinfo_data; 2) further crashes the system; 3) trigger kdump, then we obviously will fail to recognize the crash context correctly due to the corrupted vmcoreinfo. Now except for vmcoreinfo, all the crash data is well protected(including the cpu note which is fully updated in the crash path, thus its correctness is guaranteed). Given that vmcoreinfo data is a large chunk prepared for kdump, we better protect it as well. To solve this, we relocate and copy vmcoreinfo_data to the crash memory when kdump is loading via kexec syscalls. Because the whole crash memory will be protected by existing arch_kexec_protect_crashkres() mechanism, we naturally protect vmcoreinfo_data from write(even read) access under kernel direct mapping after kdump is loaded. Since kdump is usually loaded at the very early stage after boot, we can trust the correctness of the vmcoreinfo data copied. On the other hand, we still need to operate the vmcoreinfo safe copy when crash happens to generate vmcoreinfo_note again, we rely on vmap() to map out a new kernel virtual address and update to use this new one instead in the following crash_save_vmcoreinfo(). BTW, we do not touch vmcoreinfo_note, because it will be fully updated using the protected vmcoreinfo_data after crash which is surely correct just like the cpu crash note. Link: http://lkml.kernel.org/r/1493281021-20737-3-git-send-email-xlpang@redhat.com Signed-off-by: Xunlei Pang <xlpang@redhat.com> Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Young <dyoung@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Hari Bathini <hbathini@linux.vnet.ibm.com> Cc: Juergen Gross <jgross@suse.com> Cc: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kimage_file_prepare_segments(): don't open-code memdup_user()Al Viro2017-06-301-10/+4
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* kexec, x86/purgatory: Unbreak it and clean it upThomas Gleixner2017-03-101-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The purgatory code defines global variables which are referenced via a symbol lookup in the kexec code (core and arch). A recent commit addressing sparse warnings made these static and thereby broke kexec_file. Why did this happen? Simply because the whole machinery is undocumented and lacks any form of forward declarations. The variable names are unspecific and lack a prefix, so adding forward declarations creates shadow variables in the core code. Aside of that the code relies on magic constants and duplicate struct definitions with no way to ensure that these things stay in sync. The section placement of the purgatory variables happened by chance and not by design. Unbreak kexec and cleanup the mess: - Add proper forward declarations and document the usage - Use common struct definition - Use the proper common defines instead of magic constants - Add a purgatory_ prefix to have a proper name space - Use ARRAY_SIZE() instead of a homebrewn reimplementation - Add proper sections to the purgatory variables [ From Mike ] Fixes: 72042a8c7b01 ("x86/purgatory: Make functions and variables static") Reported-by: Mike Galbraith <<efault@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Nicholas Mc Guire <der.herr@hofr.at> Cc: Borislav Petkov <bp@alien8.de> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Tobin C. Harding" <me@tobin.cc> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1703101315140.3681@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* ima: on soft reboot, save the measurement listMimi Zohar2016-12-201-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | The TPM PCRs are only reset on a hard reboot. In order to validate a TPM's quote after a soft reboot (eg. kexec -e), the IMA measurement list of the running kernel must be saved and restored on boot. This patch uses the kexec buffer passing mechanism to pass the serialized IMA binary_runtime_measurements to the next kernel. Link: http://lkml.kernel.org/r/1480554346-29071-7-git-send-email-zohar@linux.vnet.ibm.com Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Dmitry Kasatkin <dmitry.kasatkin@gmail.com> Cc: Andreas Steffen <andreas.steffen@strongswan.org> Cc: Josh Sklar <sklar@linux.vnet.ibm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Stewart Smith <stewart@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec_file: Factor out kexec_locate_mem_hole from kexec_add_buffer.Thiago Jung Bauermann2016-11-301-5/+20
| | | | | | | | | kexec_locate_mem_hole will be used by the PowerPC kexec_file_load implementation to find free memory for the purgatory stack. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* kexec_file: Change kexec_add_buffer to take kexec_buf as argument.Thiago Jung Bauermann2016-11-301-48/+40
| | | | | | | | | | | | | | This is done to simplify the kexec_add_buffer argument list. Adapt all callers to set up a kexec_buf to pass to kexec_add_buffer. In addition, change the type of kexec_buf.buffer from char * to void *. There is no particular reason for it to be a char *, and the change allows us to get rid of 3 existing casts to char * in the code. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* kexec_file: Allow arch-specific memory walking for kexec_add_bufferThiago Jung Bauermann2016-11-301-8/+22
| | | | | | | | | | | Allow architectures to specify a different memory walking function for kexec_add_buffer. x86 uses iomem to track reserved memory ranges, but PowerPC uses the memblock subsystem. Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Dave Young <dyoung@redhat.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
* kexec: fix double-free when failing to relocate the purgatoryThiago Jung Bauermann2016-09-021-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If kexec_apply_relocations fails, kexec_load_purgatory frees pi->sechdrs and pi->purgatory_buf. This is redundant, because in case of error kimage_file_prepare_segments calls kimage_file_post_load_cleanup, which will also free those buffers. This causes two warnings like the following, one for pi->sechdrs and the other for pi->purgatory_buf: kexec-bzImage64: Loading purgatory failed ------------[ cut here ]------------ WARNING: CPU: 1 PID: 2119 at mm/vmalloc.c:1490 __vunmap+0xc1/0xd0 Trying to vfree() nonexistent vm area (ffffc90000e91000) Modules linked in: CPU: 1 PID: 2119 Comm: kexec Not tainted 4.8.0-rc3+ #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x4d/0x65 __warn+0xcb/0xf0 warn_slowpath_fmt+0x4f/0x60 ? find_vmap_area+0x19/0x70 ? kimage_file_post_load_cleanup+0x47/0xb0 __vunmap+0xc1/0xd0 vfree+0x2e/0x70 kimage_file_post_load_cleanup+0x5e/0xb0 SyS_kexec_file_load+0x448/0x680 ? putname+0x54/0x60 ? do_sys_open+0x190/0x1f0 entry_SYSCALL_64_fastpath+0x13/0x8f ---[ end trace 158bb74f5950ca2b ]--- Fix by setting pi->sechdrs an pi->purgatory_buf to NULL, since vfree won't try to free a NULL pointer. Link: http://lkml.kernel.org/r/1472083546-23683-1-git-send-email-bauerman@linux.vnet.ibm.com Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec: introduce a protection mechanism for the crashkernel reserved memoryXunlei Pang2016-05-241-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For the cases that some kernel (module) path stamps the crash reserved memory(already mapped by the kernel) where has been loaded the second kernel data, the kdump kernel will probably fail to boot when panic happens (or even not happens) leaving the culprit at large, this is unacceptable. The patch introduces a mechanism for detecting such cases: 1) After each crash kexec loading, it simply marks the reserved memory regions readonly since we no longer access it after that. When someone stamps the region, the first kernel will panic and trigger the kdump. The weak arch_kexec_protect_crashkres() is introduced to do the actual protection. 2) To allow multiple loading, once 1) was done we also need to remark the reserved memory to readwrite each time a system call related to kdump is made. The weak arch_kexec_unprotect_crashkres() is introduced to do the actual protection. The architecture can make its specific implementation by overriding arch_kexec_protect_crashkres() and arch_kexec_unprotect_crashkres(). Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Cc: Minfei Huang <mhuang@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Baoquan He <bhe@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'next' of ↵Linus Torvalds2016-03-171-64/+9
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security Pull security layer updates from James Morris: "There are a bunch of fixes to the TPM, IMA, and Keys code, with minor fixes scattered across the subsystem. IMA now requires signed policy, and that policy is also now measured and appraised" * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (67 commits) X.509: Make algo identifiers text instead of enum akcipher: Move the RSA DER encoding check to the crypto layer crypto: Add hash param to pkcs1pad sign-file: fix build with CMS support disabled MAINTAINERS: update tpmdd urls MODSIGN: linux/string.h should be #included to get memcpy() certs: Fix misaligned data in extra certificate list X.509: Handle midnight alternative notation in GeneralizedTime X.509: Support leap seconds Handle ISO 8601 leap seconds and encodings of midnight in mktime64() X.509: Fix leap year handling again PKCS#7: fix unitialized boolean 'want' firmware: change kernel read fail to dev_dbg() KEYS: Use the symbol value for list size, updated by scripts/insert-sys-cert KEYS: Reserve an extra certificate symbol for inserting without recompiling modsign: hide openssl output in silent builds tpm_tis: fix build warning with tpm_tis_resume ima: require signed IMA policy ima: measure and appraise the IMA policy itself ima: load policy using path ...
| * kexec: replace call to copy_file_from_fd() with kernel versionMimi Zohar2016-02-211-64/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Replace copy_file_from_fd() with kernel_read_file_from_fd(). Two new identifiers named READING_KEXEC_IMAGE and READING_KEXEC_INITRAMFS are defined for measuring, appraising or auditing the kexec image and initramfs. Changelog v3: - return -EBADF, not -ENOEXEC - identifier change - split patch, moving copy_file_from_fd() to a separate patch - split patch, moving IMA changes to a separate patch v0: - use kstat file size type loff_t, not size_t - Calculate the file hash from the in memory buffer - Dave Young Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Acked-by: Kees Cook <keescook@chromium.org> Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> Cc: Eric Biederman <ebiederm@xmission.com> Acked-by: Dave Young <dyoung@redhat.com>
* | x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem searchToshi Kani2016-01-301-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Change the callers of walk_iomem_res() scanning for the following resources by name to use walk_iomem_res_desc() instead. "ACPI Tables" "ACPI Non-volatile Storage" "Persistent Memory (legacy)" "Crash kernel" Note, the caller of walk_iomem_res() with "GART" will be removed in a later patch. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Chun-Yi <joeyli.kernel@gmail.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Don Zickus <dzickus@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Lee, Chun-Yi <joeyli.kernel@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Minfei Huang <mnfhuang@gmail.com> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Takao Indoh <indou.takao@jp.fujitsu.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: kexec@lists.infradead.org Cc: linux-arch@vger.kernel.org Cc: linux-mm <linux-mm@kvack.org> Cc: linux-nvdimm@lists.01.org Link: http://lkml.kernel.org/r/1453841853-11383-15-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | kexec: Set IORESOURCE_SYSTEM_RAM for System RAMToshi Kani2016-01-301-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Set proper ioresource flags and types for crash kernel reservation areas. Signed-off-by: Toshi Kani <toshi.kani@hpe.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Dave Young <dyoung@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Baoquan He <bhe@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: Minfei Huang <mnfhuang@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: kexec@lists.infradead.org Cc: linux-arch@vger.kernel.org Cc: linux-mm <linux-mm@kvack.org> Link: http://lkml.kernel.org/r/1453841853-11383-8-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILEXunlei Pang2016-01-211-0/+2
| | | | | | | | | | | | | | Move the stuff currently only used by the kexec file code within CONFIG_KEXEC_FILE (and CONFIG_KEXEC_VERIFY_SIG). Also move internal "struct kexec_sha_region" and "struct kexec_buf" into "kexec_internal.h". Signed-off-by: Xunlei Pang <xlpang@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Dave Young <dyoung@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec: use file name as the output message prefixMinfei Huang2015-11-071-0/+2
| | | | | | | | | | | | | | | | | | | | | kexec output message misses the prefix "kexec", when Dave Young split the kexec code. Now, we use file name as the output message prefix. Currently, the format of output message: [ 140.290795] SYSC_kexec_load: hello, world [ 140.291534] kexec: sanity_check_segment_list: hello, world Ideally, the format of output message: [ 30.791503] kexec: SYSC_kexec_load, Hello, world [ 79.182752] kexec_core: sanity_check_segment_list, Hello, world Remove the custom prefix "kexec" in output message. Signed-off-by: Minfei Huang <mnfhuang@gmail.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kexec: split kexec_file syscall code to kexec_file.cDave Young2015-09-101-0/+1045
Split kexec_file syscall related code to another file kernel/kexec_file.c so that the #ifdef CONFIG_KEXEC_FILE in kexec.c can be dropped. Sharing variables and functions are moved to kernel/kexec_internal.h per suggestion from Vivek and Petr. [akpm@linux-foundation.org: fix bisectability] [akpm@linux-foundation.org: declare the various arch_kexec functions] [akpm@linux-foundation.org: fix build] Signed-off-by: Dave Young <dyoung@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Petr Tesarik <ptesarik@suse.cz> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Josh Boyer <jwboyer@fedoraproject.org> Cc: David Howells <dhowells@redhat.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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