kernel/linux.git/lib, branch v5.4.33

xarray: Fix early termination of xas_for_each_marked

2020-04-17T08:50:18+00:00

commit 7e934cf5ace1dceeb804f7493fa28bb697ed3c52 upstream. xas_for_each_marked() is using entry == NULL as a termination condition of the iteration. When xas_for_each_marked() is used protected only by RCU, this can however race with xas_store(xas, NULL) in the following way: TASK1 TASK2 page_cache_delete() find_get_pages_range_tag() xas_for_each_marked() xas_find_marked() off = xas_find_chunk() xas_store(&xas, NULL) xas_init_marks(&xas); ... rcu_assign_pointer(*slot, NULL); entry = xa_entry(off); And thus xas_for_each_marked() terminates prematurely possibly leading to missed entries in the iteration (translating to missing writeback of some pages or a similar problem). If we find a NULL entry that has been marked, skip it (unless we're trying to allocate an entry). Reported-by: Jan Kara CC: stable@vger.kernel.org Fixes: ef8e5717db01 ("page cache: Convert delete_batch to XArray") Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Greg Kroah-Hartman

XArray: Fix xas_pause for large multi-index entries

2020-04-17T08:50:18+00:00

commit c36d451ad386b34f452fc3c8621ff14b9eaa31a6 upstream. Inspired by the recent Coverity report, I looked for other places where the offset wasn't being converted to an unsigned long before being shifted, and I found one in xas_pause() when the entry being paused is of order >32. Fixes: b803b42823d0 ("xarray: Add XArray iterators") Signed-off-by: Matthew Wilcox (Oracle) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

uapi: rename ext2_swab() to swab() and share globally in swab.h

2020-04-13T08:48:07+00:00

commit d5767057c9a76a29f073dad66b7fa12a90e8c748 upstream. ext2_swab() is defined locally in lib/find_bit.c However it is not specific to ext2, neither to bitmaps. There are many potential users of it, so rename it to just swab() and move to include/uapi/linux/swab.h ABI guarantees that size of unsigned long corresponds to BITS_PER_LONG, therefore drop unneeded cast. Link: http://lkml.kernel.org/r/20200103202846.21616-1-yury.norov@gmail.com Signed-off-by: Yury Norov Cc: Allison Randal Cc: Joe Perches Cc: Thomas Gleixner Cc: William Breathitt Gray Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

XArray: Fix xa_find_next for large multi-index entries

2020-04-08T07:08:40+00:00

[ Upstream commit bd40b17ca49d7d110adf456e647701ce74de2241 ] Coverity pointed out that xas_sibling() was shifting xa_offset without promoting it to an unsigned long first, so the shift could cause an overflow and we'd get the wrong answer. The fix is obvious, and the new test-case provokes UBSAN to report an error: runtime error: shift exponent 60 is too large for 32-bit type 'int' Fixes: 19c30f4dd092 ("XArray: Fix xa_find_after with multi-index entries") Reported-by: Bjorn Helgaas Reported-by: Kees Cook Signed-off-by: Matthew Wilcox (Oracle) Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin

kbuild: move headers_check rule to usr/include/Makefile

2020-03-05T15:43:47+00:00

commit 7ecaf069da52e472d393f03e79d721aabd724166 upstream. Currently, some sanity checks for uapi headers are done by scripts/headers_check.pl, which is wired up to the 'headers_check' target in the top Makefile. It is true compiling headers has better test coverage, but there are still several headers excluded from the compile test. I like to keep headers_check.pl for a while, but we can delete a lot of code by moving the build rule to usr/include/Makefile. Signed-off-by: Masahiro Yamada Signed-off-by: Greg Kroah-Hartman

lib/stackdepot.c: fix global out-of-bounds in stack_slabs

2020-02-28T16:22:20+00:00

commit 305e519ce48e935702c32241f07d393c3c8fed3e upstream. Walter Wu has reported a potential case in which init_stack_slab() is called after stack_slabs[STACK_ALLOC_MAX_SLABS - 1] has already been initialized. In that case init_stack_slab() will overwrite stack_slabs[STACK_ALLOC_MAX_SLABS], which may result in a memory corruption. Link: http://lkml.kernel.org/r/20200218102950.260263-1-glider@google.com Fixes: cd11016e5f521 ("mm, kasan: stackdepot implementation. Enable stackdepot for SLAB") Signed-off-by: Alexander Potapenko Reported-by: Walter Wu Cc: Dmitry Vyukov Cc: Matthias Brugger Cc: Thomas Gleixner Cc: Josh Poimboeuf Cc: Kate Stewart Cc: Greg Kroah-Hartman Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

lib/scatterlist.c: adjust indentation in __sg_alloc_table

2020-02-24T07:37:00+00:00

[ Upstream commit 4e456fee215677584cafa7f67298a76917e89c64 ] Clang warns: ../lib/scatterlist.c:314:5: warning: misleading indentation; statement is not part of the previous 'if' [-Wmisleading-indentation] return -ENOMEM; ^ ../lib/scatterlist.c:311:4: note: previous statement is here if (prv) ^ 1 warning generated. This warning occurs because there is a space before the tab on this line. Remove it so that the indentation is consistent with the Linux kernel coding style and clang no longer warns. Link: http://lkml.kernel.org/r/20191218033606.11942-1-natechancellor@gmail.com Link: https://github.com/ClangBuiltLinux/linux/issues/830 Fixes: edce6820a9fd ("scatterlist: prevent invalid free when alloc fails") Signed-off-by: Nathan Chancellor Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

debugobjects: Fix various data races

2020-02-24T07:36:52+00:00

[ Upstream commit 35fd7a637c42bb54ba4608f4d40ae6e55fc88781 ] The counters obj_pool_free, and obj_nr_tofree, and the flag obj_freeing are read locklessly outside the pool_lock critical sections. If read with plain accesses, this would result in data races. This is addressed as follows: * reads outside critical sections become READ_ONCE()s (pairing with WRITE_ONCE()s added); * writes become WRITE_ONCE()s (pairing with READ_ONCE()s added); since writes happen inside critical sections, only the write and not the read of RMWs needs to be atomic, thus WRITE_ONCE(var, var +/- X) is sufficient. The data races were reported by KCSAN: BUG: KCSAN: data-race in __free_object / fill_pool write to 0xffffffff8beb04f8 of 4 bytes by interrupt on cpu 1: __free_object+0x1ee/0x8e0 lib/debugobjects.c:404 __debug_check_no_obj_freed+0x199/0x330 lib/debugobjects.c:969 debug_check_no_obj_freed+0x3c/0x44 lib/debugobjects.c:994 slab_free_hook mm/slub.c:1422 [inline] read to 0xffffffff8beb04f8 of 4 bytes by task 1 on cpu 2: fill_pool+0x3d/0x520 lib/debugobjects.c:135 __debug_object_init+0x3c/0x810 lib/debugobjects.c:536 debug_object_init lib/debugobjects.c:591 [inline] debug_object_activate+0x228/0x320 lib/debugobjects.c:677 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] BUG: KCSAN: data-race in __debug_object_init / fill_pool read to 0xffffffff8beb04f8 of 4 bytes by task 10 on cpu 6: fill_pool+0x3d/0x520 lib/debugobjects.c:135 __debug_object_init+0x3c/0x810 lib/debugobjects.c:536 debug_object_init_on_stack+0x39/0x50 lib/debugobjects.c:606 init_timer_on_stack_key kernel/time/timer.c:742 [inline] write to 0xffffffff8beb04f8 of 4 bytes by task 1 on cpu 3: alloc_object lib/debugobjects.c:258 [inline] __debug_object_init+0x717/0x810 lib/debugobjects.c:544 debug_object_init lib/debugobjects.c:591 [inline] debug_object_activate+0x228/0x320 lib/debugobjects.c:677 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] BUG: KCSAN: data-race in free_obj_work / free_object read to 0xffffffff9140c190 of 4 bytes by task 10 on cpu 6: free_object+0x4b/0xd0 lib/debugobjects.c:426 debug_object_free+0x190/0x210 lib/debugobjects.c:824 destroy_timer_on_stack kernel/time/timer.c:749 [inline] write to 0xffffffff9140c190 of 4 bytes by task 93 on cpu 1: free_obj_work+0x24f/0x480 lib/debugobjects.c:313 process_one_work+0x454/0x8d0 kernel/workqueue.c:2264 worker_thread+0x9a/0x780 kernel/workqueue.c:2410 Reported-by: Qian Cai Signed-off-by: Marco Elver Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/20200116185529.11026-1-elver@google.com Signed-off-by: Sasha Levin

raid6/test: fix a compilation warning

2020-02-24T07:36:47+00:00

[ Upstream commit 5e5ac01c2b8802921fee680518a986011cb59820 ] The compilation warning is redefination showed as following: In file included from tables.c:2: ../../../include/linux/export.h:180: warning: "EXPORT_SYMBOL" redefined #define EXPORT_SYMBOL(sym) __EXPORT_SYMBOL(sym, "") In file included from tables.c:1: ../../../include/linux/raid/pq.h:61: note: this is the location of the previous definition #define EXPORT_SYMBOL(sym) Fixes: 69a94abb82ee ("export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols") Signed-off-by: Zhengyuan Liu Signed-off-by: Song Liu Signed-off-by: Sasha Levin

lib/test_kasan.c: fix memory leak in kmalloc_oob_krealloc_more()

2020-02-11T12:35:14+00:00

commit 3e21d9a501bf99aee2e5835d7f34d8c823f115b5 upstream. In case memory resources for _ptr2_ were allocated, release them before return. Notice that in case _ptr1_ happens to be NULL, krealloc() behaves exactly like kmalloc(). Addresses-Coverity-ID: 1490594 ("Resource leak") Link: http://lkml.kernel.org/r/20200123160115.GA4202@embeddedor Fixes: 3f15801cdc23 ("lib: add kasan test module") Signed-off-by: Gustavo A. R. Silva Reviewed-by: Dmitry Vyukov Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman