kernel/linux.git/lib, branch v6.1.140

ubsan: Fix panic from test_ubsan_out_of_bounds

2025-05-02T05:47:08+00:00

[ Upstream commit 9b044614be12d78d3a93767708b8d02fb7dfa9b0 ] Running lib_ubsan.ko on arm64 (without CONFIG_UBSAN_TRAP) panics the kernel: [ 31.616546] Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: test_ubsan_out_of_bounds+0x158/0x158 [test_ubsan] [ 31.646817] CPU: 3 UID: 0 PID: 179 Comm: insmod Not tainted 6.15.0-rc2 #1 PREEMPT [ 31.648153] Hardware name: linux,dummy-virt (DT) [ 31.648970] Call trace: [ 31.649345] show_stack+0x18/0x24 (C) [ 31.650960] dump_stack_lvl+0x40/0x84 [ 31.651559] dump_stack+0x18/0x24 [ 31.652264] panic+0x138/0x3b4 [ 31.652812] __ktime_get_real_seconds+0x0/0x10 [ 31.653540] test_ubsan_load_invalid_value+0x0/0xa8 [test_ubsan] [ 31.654388] init_module+0x24/0xff4 [test_ubsan] [ 31.655077] do_one_initcall+0xd4/0x280 [ 31.655680] do_init_module+0x58/0x2b4 That happens because the test corrupts other data in the stack: 400: d5384108 mrs x8, sp_el0 404: f9426d08 ldr x8, [x8, #1240] 408: f85f83a9 ldur x9, [x29, #-8] 40c: eb09011f cmp x8, x9 410: 54000301 b.ne 470 // b.any As there is no guarantee the compiler will order the local variables as declared in the module: volatile char above[4] = { }; /* Protect surrounding memory. */ volatile int arr[4]; volatile char below[4] = { }; /* Protect surrounding memory. */ There is another problem where the out-of-bound index is 5 which is larger than the extra surrounding memory for protection. So, use a struct to enforce the ordering, and fix the index to be 4. Also, remove some of the volatiles and rely on OPTIMIZER_HIDE_VAR() Signed-off-by: Mostafa Saleh Link: https://lore.kernel.org/r/20250415203354.4109415-1-smostafa@google.com Signed-off-by: Kees Cook Signed-off-by: Sasha Levin

string: Add load_unaligned_zeropad() code path to sized_strscpy()

2025-04-25T08:43:55+00:00

commit d94c12bd97d567de342fd32599e7cd9e50bfa140 upstream. The call to read_word_at_a_time() in sized_strscpy() is problematic with MTE because it may trigger a tag check fault when reading across a tag granule (16 bytes) boundary. To make this code MTE compatible, let's start using load_unaligned_zeropad() on architectures where it is available (i.e. architectures that define CONFIG_DCACHE_WORD_ACCESS). Because load_unaligned_zeropad() takes care of page boundaries as well as tag granule boundaries, also disable the code preventing crossing page boundaries when using load_unaligned_zeropad(). Signed-off-by: Peter Collingbourne Link: https://linux-review.googlesource.com/id/If4b22e43b5a4ca49726b4bf98ada827fdf755548 Fixes: 94ab5b61ee16 ("kasan, arm64: enable CONFIG_KASAN_HW_TAGS") Cc: stable@vger.kernel.org Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20250403000703.2584581-2-pcc@google.com Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman

lib: scatterlist: fix sg_split_phys to preserve original scatterlist offsets

2025-04-25T08:43:41+00:00

commit 8b46fdaea819a679da176b879e7b0674a1161a5e upstream. The split_sg_phys function was incorrectly setting the offsets of all scatterlist entries (except the first) to 0. Only the first scatterlist entry's offset and length needs to be modified to account for the skip. Setting the rest entries' offsets to 0 could lead to incorrect data access. I am using this function in a crypto driver that I'm currently developing (not yet sent to mailing list). During testing, it was observed that the output scatterlists (except the first one) contained incorrect garbage data. I narrowed this issue down to the call of sg_split(). Upon debugging inside this function, I found that this resetting of offset is the cause of the problem, causing the subsequent scatterlists to point to incorrect memory locations in a page. By removing this code, I am obtaining expected data in all the split output scatterlists. Thus, this was indeed causing observable runtime effects! This patch removes the offending code, ensuring that the page offsets in the input scatterlist are preserved in the output scatterlist. Link: https://lkml.kernel.org/r/20250319111437.1969903-1-t-pratham@ti.com Fixes: f8bcbe62acd0 ("lib: scatterlist: add sg splitting function") Signed-off-by: T Pratham Cc: Robert Jarzmik Cc: Jens Axboe Cc: Kamlesh Gurudasani Cc: Praneeth Bajjuri Cc: Vignesh Raghavendra Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

kunit/overflow: Fix UB in overflow_allocation_test

2025-04-10T12:33:42+00:00

commit 92e9bac18124682c4b99ede9ee3bcdd68f121e92 upstream. The 'device_name' array doesn't exist out of the 'overflow_allocation_test' function scope. However, it is being used as a driver name when calling 'kunit_driver_create' from 'kunit_device_register'. It produces the kernel panic with KASAN enabled. Since this variable is used in one place only, remove it and pass the device name into kunit_device_register directly as an ascii string. Signed-off-by: Ivan Orlov Reviewed-by: David Gow Link: https://lore.kernel.org/r/20240815000431.401869-1-ivan.orlov0322@gmail.com Signed-off-by: Kees Cook Signed-off-by: Jianqi Ren Signed-off-by: He Zhe Signed-off-by: Greg Kroah-Hartman

lib: 842: Improve error handling in sw842_compress()

2025-04-10T12:33:34+00:00

[ Upstream commit af324dc0e2b558678aec42260cce38be16cc77ca ] The static code analysis tool "Coverity Scan" pointed the following implementation details out for further development considerations: CID 1309755: Unused value In sw842_compress: A value assigned to a variable is never used. (CWE-563) returned_value: Assigning value from add_repeat_template(p, repeat_count) to ret here, but that stored value is overwritten before it can be used. Conclusion: Add error handling for the return value from an add_repeat_template() call. Fixes: 2da572c959dd ("lib: add software 842 compression/decompression") Signed-off-by: Tanya Agarwal Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

lib/buildid: Handle memfd_secret() files in build_id_parse()

2025-03-28T20:58:57+00:00

commit 5ac9b4e935dfc6af41eee2ddc21deb5c36507a9f upstream. >From memfd_secret(2) manpage: The memory areas backing the file created with memfd_secret(2) are visible only to the processes that have access to the file descriptor. The memory region is removed from the kernel page tables and only the page tables of the processes holding the file descriptor map the corresponding physical memory. (Thus, the pages in the region can't be accessed by the kernel itself, so that, for example, pointers to the region can't be passed to system calls.) We need to handle this special case gracefully in build ID fetching code. Return -EFAULT whenever secretmem file is passed to build_id_parse() family of APIs. Original report and repro can be found in [0]. [0] https://lore.kernel.org/bpf/ZwyG8Uro%2FSyTXAni@ly-workstation/ Fixes: de3ec364c3c3 ("lib/buildid: add single folio-based file reader abstraction") Reported-by: Yi Lai Suggested-by: Shakeel Butt Signed-off-by: Andrii Nakryiko Signed-off-by: Daniel Borkmann Acked-by: Shakeel Butt Link: https://lore.kernel.org/bpf/20241017175431.6183-A-hca@linux.ibm.com Link: https://lore.kernel.org/bpf/20241017174713.2157873-1-andrii@kernel.org [ Chen Linxuan: backport same logic without folio-based changes ] Fixes: 88a16a130933 ("perf: Add build id data in mmap2 event") Signed-off-by: Chen Linxuan Signed-off-by: Greg Kroah-Hartman

maple_tree: simplify split calculation

2025-02-21T12:49:55+00:00

commit 4f6a6bed0bfef4b966f076f33eb4f5547226056a upstream. Patch series "simplify split calculation", v3. This patch (of 3): The current calculation for splitting nodes tries to enforce a minimum span on the leaf nodes. This code is complex and never worked correctly to begin with, due to the min value being passed as 0 for all leaves. The calculation should just split the data as equally as possible between the new nodes. Note that b_end will be one more than the data, so the left side is still favoured in the calculation. The current code may also lead to a deficient node by not leaving enough data for the right side of the split. This issue is also addressed with the split calculation change. [Liam.Howlett@Oracle.com: rephrase the change log] Link: https://lkml.kernel.org/r/20241113031616.10530-1-richard.weiyang@gmail.com Link: https://lkml.kernel.org/r/20241113031616.10530-2-richard.weiyang@gmail.com Fixes: 54a611b60590 ("Maple Tree: add new data structure") Signed-off-by: Wei Yang Reviewed-by: Liam R. Howlett Cc: Sidhartha Kumar Cc: Lorenzo Stoakes Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

maple_tree: fix static analyser cppcheck issue

2025-02-21T12:49:55+00:00

commit 5729e06c819184b7ba40869c1ad53e1a463040b2 upstream. Patch series "Maple tree mas_{next,prev}_range() and cleanup", v4. This patchset contains a number of clean ups to the code to make it more usable (next/prev range), the addition of debug output formatting, the addition of printing the maple state information in the WARN_ON/BUG_ON code. There is also work done here to keep nodes active during iterations to reduce the necessity of re-walking the tree. Finally, there is a new interface added to move to the next or previous range in the tree, even if it is empty. The organisation of the patches is as follows: 0001-0004 - Small clean ups 0005-0018 - Additional debug options and WARN_ON/BUG_ON changes 0019 - Test module __init and __exit addition 0020-0021 - More functional clean ups 0022-0026 - Changes to keep nodes active 0027-0034 - Add new mas_{prev,next}_range() 0035 - Use new mas_{prev,next}_range() in mmap_region() This patch (of 35): Static analyser of the maple tree code noticed that the split variable is being used to dereference into an array prior to checking the variable itself. Fix this issue by changing the order of the statement to check the variable first. Link: https://lkml.kernel.org/r/20230518145544.1722059-1-Liam.Howlett@oracle.com Link: https://lkml.kernel.org/r/20230518145544.1722059-2-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Reported-by: David Binderman Reviewed-by: Peng Zhang Cc: Sergey Senozhatsky Cc: Vernon Yang Cc: Wei Yang Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

lockdep: Fix upper limit for LOCKDEP_*_BITS configs

2025-02-21T12:49:29+00:00

[ Upstream commit e638072e61726cae363d48812815197a2a0e097f ] Lockdep has a set of configs used to determine the size of the static arrays that it uses. However, the upper limit that was initially setup for these configs is too high (30 bit shift). This equates to several GiB of static memory for individual symbols. Using such high values leads to linker errors: $ make defconfig $ ./scripts/config -e PROVE_LOCKING --set-val LOCKDEP_BITS 30 $ make olddefconfig all [...] ld: kernel image bigger than KERNEL_IMAGE_SIZE ld: section .bss VMA wraps around address space Adjust the upper limits to the maximum values that avoid these issues. The need for anything more, likely points to a problem elsewhere. Note that LOCKDEP_CHAINS_BITS was intentionally left out as its upper limit had a different symptom and has already been fixed [1]. Reported-by: J. R. Okajima Closes: https://lore.kernel.org/all/30795.1620913191@jrobl/ [1] Cc: Peter Zijlstra Cc: Boqun Feng Cc: Ingo Molnar Cc: Waiman Long Cc: Will Deacon Acked-by: Waiman Long Signed-off-by: Carlos Llamas Signed-off-by: Boqun Feng Link: https://lore.kernel.org/r/20241024183631.643450-2-cmllamas@google.com Signed-off-by: Sasha Levin

lib: stackinit: hide never-taken branch from compiler

2024-12-14T18:54:37+00:00

commit 5c3793604f91123bf49bc792ce697a0bef4c173c upstream. The never-taken branch leads to an invalid bounds condition, which is by design. To avoid the unwanted warning from the compiler, hide the variable from the optimizer. ../lib/stackinit_kunit.c: In function 'do_nothing_u16_zero': ../lib/stackinit_kunit.c:51:49: error: array subscript 1 is outside array bounds of 'u16[0]' {aka 'short unsigned int[]'} [-Werror=array-bounds=] 51 | #define DO_NOTHING_RETURN_SCALAR(ptr) *(ptr) | ^~~~~~ ../lib/stackinit_kunit.c:219:24: note: in expansion of macro 'DO_NOTHING_RETURN_SCALAR' 219 | return DO_NOTHING_RETURN_ ## which(ptr + 1); \ | ^~~~~~~~~~~~~~~~~~ Link: https://lkml.kernel.org/r/20241117113813.work.735-kees@kernel.org Signed-off-by: Kees Cook Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman