kernel/linux.git/lib, branch v5.15.172

lib/buildid: harden build ID parsing logic

2024-10-17T13:11:45+00:00

[ Upstream commit 905415ff3ffb1d7e5afa62bacabd79776bd24606 ] Harden build ID parsing logic, adding explicit READ_ONCE() where it's important to have a consistent value read and validated just once. Also, as pointed out by Andi Kleen, we need to make sure that entire ELF note is within a page bounds, so move the overflow check up and add an extra note_size boundaries validation. Fixes tag below points to the code that moved this code into lib/buildid.c, and then subsequently was used in perf subsystem, making this code exposed to perf_event_open() users in v5.12+. Cc: stable@vger.kernel.org Reviewed-by: Eduard Zingerman Reviewed-by: Jann Horn Suggested-by: Andi Kleen Fixes: bd7525dacd7e ("bpf: Move stack_map_get_build_id into lib") Signed-off-by: Andrii Nakryiko Link: https://lore.kernel.org/r/20240829174232.3133883-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin

build-id: require program headers to be right after ELF header

2024-10-17T13:11:45+00:00

[ Upstream commit 961a2851324561caed579764ffbee3db82b32829 ] Neither ELF spec not ELF loader require program header to be placed right after ELF header, but build-id code very much assumes such placement: See find_get_page(vma->vm_file->f_mapping, 0); line and checks against PAGE_SIZE. Returns errors for now until someone rewrites build-id parser to be more inline with load_elf_binary(). Link: https://lkml.kernel.org/r/d58bc281-6ca7-467a-9a64-40fa214bd63e@p183 Signed-off-by: Alexey Dobriyan Reviewed-by: Jiri Olsa Signed-off-by: Andrew Morton Stable-dep-of: 905415ff3ffb ("lib/buildid: harden build ID parsing logic") Signed-off-by: Sasha Levin

debugobjects: Fix conditions in fill_pool()

2024-10-17T13:11:14+00:00

commit 684d28feb8546d1e9597aa363c3bfcf52fe250b7 upstream. fill_pool() uses 'obj_pool_min_free' to decide whether objects should be handed back to the kmem cache. But 'obj_pool_min_free' records the lowest historical value of the number of objects in the object pool and not the minimum number of objects which should be kept in the pool. Use 'debug_objects_pool_min_level' instead, which holds the minimum number which was scaled to the number of CPUs at boot time. [ tglx: Massage change log ] Fixes: d26bf5056fc0 ("debugobjects: Reduce number of pool_lock acquisitions in fill_pool()") Fixes: 36c4ead6f6df ("debugobjects: Add global free list and the counter") Signed-off-by: Zhen Lei Signed-off-by: Thomas Gleixner Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/20240904133944.2124-3-thunder.leizhen@huawei.com Signed-off-by: Greg Kroah-Hartman

xz: cleanup CRC32 edits from 2018

2024-10-17T13:10:56+00:00

[ Upstream commit 2ee96abef214550d9e92f5143ee3ac1fd1323e67 ] In 2018, a dependency on was added to avoid duplicating the same constant in multiple files. Two months later it was found to be a bad idea and the definition of CRC32_POLY_LE macro was moved into xz_private.h to avoid including . xz_private.h is a wrong place for it too. Revert back to the upstream version which has the poly in xz_crc32_init() in xz_crc32.c. Link: https://lkml.kernel.org/r/20240721133633.47721-10-lasse.collin@tukaani.org Fixes: faa16bc404d7 ("lib: Use existing define with polynomial") Fixes: 242cdad873a7 ("lib/xz: Put CRC32_POLY_LE in xz_private.h") Signed-off-by: Lasse Collin Reviewed-by: Sam James Tested-by: Michael Ellerman (powerpc) Cc: Krzysztof Kozlowski Cc: Herbert Xu Cc: Joel Stanley Cc: Albert Ou Cc: Catalin Marinas Cc: Emil Renner Berthing Cc: Greg Kroah-Hartman Cc: Jonathan Corbet Cc: Jubin Zhong Cc: Jules Maselbas Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Randy Dunlap Cc: Rui Li Cc: Simon Glass Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

lib/generic-radix-tree.c: Fix rare race in __genradix_ptr_alloc()

2024-09-12T09:07:50+00:00

[ Upstream commit b2f11c6f3e1fc60742673b8675c95b78447f3dae ] If we need to increase the tree depth, allocate a new node, and then race with another thread that increased the tree depth before us, we'll still have a preallocated node that might be used later. If we then use that node for a new non-root node, it'll still have a pointer to the old root instead of being zeroed - fix this by zeroing it in the cmpxchg failure path. Signed-off-by: Kent Overstreet Signed-off-by: Sasha Levin

bitmap: introduce generic optimized bitmap_size()

2024-09-04T11:23:16+00:00

commit a37fbe666c016fd89e4460d0ebfcea05baba46dc upstream. The number of times yet another open coded `BITS_TO_LONGS(nbits) * sizeof(long)` can be spotted is huge. Some generic helper is long overdue. Add one, bitmap_size(), but with one detail. BITS_TO_LONGS() uses DIV_ROUND_UP(). The latter works well when both divident and divisor are compile-time constants or when the divisor is not a pow-of-2. When it is however, the compilers sometimes tend to generate suboptimal code (GCC 13): 48 83 c0 3f add $0x3f,%rax 48 c1 e8 06 shr $0x6,%rax 48 8d 14 c5 00 00 00 00 lea 0x0(,%rax,8),%rdx %BITS_PER_LONG is always a pow-2 (either 32 or 64), but GCC still does full division of `nbits + 63` by it and then multiplication by 8. Instead of BITS_TO_LONGS(), use ALIGN() and then divide by 8. GCC: 8d 50 3f lea 0x3f(%rax),%edx c1 ea 03 shr $0x3,%edx 81 e2 f8 ff ff 1f and $0x1ffffff8,%edx Now it shifts `nbits + 63` by 3 positions (IOW performs fast division by 8) and then masks bits[2:0]. bloat-o-meter: add/remove: 0/0 grow/shrink: 20/133 up/down: 156/-773 (-617) Clang does it better and generates the same code before/after starting from -O1, except that with the ALIGN() approach it uses %edx and thus still saves some bytes: add/remove: 0/0 grow/shrink: 9/133 up/down: 18/-538 (-520) Note that we can't expand DIV_ROUND_UP() by adding a check and using this approach there, as it's used in array declarations where expressions are not allowed. Add this helper to tools/ as well. Reviewed-by: Przemek Kitszel Acked-by: Yury Norov Signed-off-by: Alexander Lobakin Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

kobject_uevent: Fix OOB access within zap_modalias_env()

2024-08-19T03:45:17+00:00

commit dd6e9894b451e7c85cceb8e9dc5432679a70e7dc upstream. zap_modalias_env() wrongly calculates size of memory block to move, so will cause OOB memory access issue if variable MODALIAS is not the last one within its @env parameter, fixed by correcting size to memmove. Fixes: 9b3fa47d4a76 ("kobject: fix suppressing modalias in uevents delivered over netlink") Cc: stable@vger.kernel.org Signed-off-by: Zijun Hu Reviewed-by: Lk Sii Link: https://lore.kernel.org/r/1717074877-11352-1-git-send-email-quic_zijuhu@quicinc.com Signed-off-by: Greg Kroah-Hartman

decompress_bunzip2: fix rare decompression failure

2024-08-19T03:45:16+00:00

commit bf6acd5d16057d7accbbb1bf7dc6d8c56eeb4ecc upstream. The decompression code parses a huffman tree and counts the number of symbols for a given bit length. In rare cases, there may be >= 256 symbols with a given bit length, causing the unsigned char to overflow. This causes a decompression failure later when the code tries and fails to find the bit length for a given symbol. Since the maximum number of symbols is 258, use unsigned short instead. Link: https://lkml.kernel.org/r/20240717162016.1514077-1-ross.lagerwall@citrix.com Fixes: bc22c17e12c1 ("bzip2/lzma: library support for gzip, bzip2 and lzma decompression") Signed-off-by: Ross Lagerwall Cc: Alain Knaff Cc: "H. Peter Anvin" Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

mlxsw: spectrum_acl_erp: Fix object nesting warning

2024-08-19T03:44:56+00:00

[ Upstream commit 97d833ceb27dc19f8777d63f90be4a27b5daeedf ] ACLs in Spectrum-2 and newer ASICs can reside in the algorithmic TCAM (A-TCAM) or in the ordinary circuit TCAM (C-TCAM). The former can contain more ACLs (i.e., tc filters), but the number of masks in each region (i.e., tc chain) is limited. In order to mitigate the effects of the above limitation, the device allows filters to share a single mask if their masks only differ in up to 8 consecutive bits. For example, dst_ip/25 can be represented using dst_ip/24 with a delta of 1 bit. The C-TCAM does not have a limit on the number of masks being used (and therefore does not support mask aggregation), but can contain a limited number of filters. The driver uses the "objagg" library to perform the mask aggregation by passing it objects that consist of the filter's mask and whether the filter is to be inserted into the A-TCAM or the C-TCAM since filters in different TCAMs cannot share a mask. The set of created objects is dependent on the insertion order of the filters and is not necessarily optimal. Therefore, the driver will periodically ask the library to compute a more optimal set ("hints") by looking at all the existing objects. When the library asks the driver whether two objects can be aggregated the driver only compares the provided masks and ignores the A-TCAM / C-TCAM indication. This is the right thing to do since the goal is to move as many filters as possible to the A-TCAM. The driver also forbids two identical masks from being aggregated since this can only happen if one was intentionally put in the C-TCAM to avoid a conflict in the A-TCAM. The above can result in the following set of hints: H1: {mask X, A-TCAM} -> H2: {mask Y, A-TCAM} // X is Y + delta H3: {mask Y, C-TCAM} -> H4: {mask Z, A-TCAM} // Y is Z + delta After getting the hints from the library the driver will start migrating filters from one region to another while consulting the computed hints and instructing the device to perform a lookup in both regions during the transition. Assuming a filter with mask X is being migrated into the A-TCAM in the new region, the hints lookup will return H1. Since H2 is the parent of H1, the library will try to find the object associated with it and create it if necessary in which case another hints lookup (recursive) will be performed. This hints lookup for {mask Y, A-TCAM} will either return H2 or H3 since the driver passes the library an object comparison function that ignores the A-TCAM / C-TCAM indication. This can eventually lead to nested objects which are not supported by the library [1]. Fix by removing the object comparison function from both the driver and the library as the driver was the only user. That way the lookup will only return exact matches. I do not have a reliable reproducer that can reproduce the issue in a timely manner, but before the fix the issue would reproduce in several minutes and with the fix it does not reproduce in over an hour. Note that the current usefulness of the hints is limited because they include the C-TCAM indication and represent aggregation that cannot actually happen. This will be addressed in net-next. [1] WARNING: CPU: 0 PID: 153 at lib/objagg.c:170 objagg_obj_parent_assign+0xb5/0xd0 Modules linked in: CPU: 0 PID: 153 Comm: kworker/0:18 Not tainted 6.9.0-rc6-custom-g70fbc2c1c38b #42 Hardware name: Mellanox Technologies Ltd. MSN3700C/VMOD0008, BIOS 5.11 10/10/2018 Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work RIP: 0010:objagg_obj_parent_assign+0xb5/0xd0 [...] Call Trace: __objagg_obj_get+0x2bb/0x580 objagg_obj_get+0xe/0x80 mlxsw_sp_acl_erp_mask_get+0xb5/0xf0 mlxsw_sp_acl_atcam_entry_add+0xe8/0x3c0 mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0 mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270 mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510 process_one_work+0x151/0x370 Fixes: 9069a3817d82 ("lib: objagg: implement optimization hints assembly and use hints for object creation") Signed-off-by: Ido Schimmel Reviewed-by: Amit Cohen Tested-by: Alexander Zubkov Signed-off-by: Petr Machata Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

lib: objagg: Fix general protection fault

2024-08-19T03:44:56+00:00

[ Upstream commit b4a3a89fffcdf09702b1f161b914e52abca1894d ] The library supports aggregation of objects into other objects only if the parent object does not have a parent itself. That is, nesting is not supported. Aggregation happens in two cases: Without and with hints, where hints are a pre-computed recommendation on how to aggregate the provided objects. Nesting is not possible in the first case due to a check that prevents it, but in the second case there is no check because the assumption is that nesting cannot happen when creating objects based on hints. The violation of this assumption leads to various warnings and eventually to a general protection fault [1]. Before fixing the root cause, error out when nesting happens and warn. [1] general protection fault, probably for non-canonical address 0xdead000000000d90: 0000 [#1] PREEMPT SMP PTI CPU: 1 PID: 1083 Comm: kworker/1:9 Tainted: G W 6.9.0-rc6-custom-gd9b4f1cca7fb #7 Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019 Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work RIP: 0010:mlxsw_sp_acl_erp_bf_insert+0x25/0x80 [...] Call Trace: mlxsw_sp_acl_atcam_entry_add+0x256/0x3c0 mlxsw_sp_acl_tcam_entry_create+0x5e/0xa0 mlxsw_sp_acl_tcam_vchunk_migrate_one+0x16b/0x270 mlxsw_sp_acl_tcam_vregion_rehash_work+0xbe/0x510 process_one_work+0x151/0x370 worker_thread+0x2cb/0x3e0 kthread+0xd0/0x100 ret_from_fork+0x34/0x50 ret_from_fork_asm+0x1a/0x30 Fixes: 9069a3817d82 ("lib: objagg: implement optimization hints assembly and use hints for object creation") Reported-by: Alexander Zubkov Signed-off-by: Ido Schimmel Reviewed-by: Amit Cohen Tested-by: Alexander Zubkov Signed-off-by: Petr Machata Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Sasha Levin