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author | Davidlohr Bueso <dave@stgolabs.net> | 2018-06-15 01:27:51 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-06-15 01:55:25 +0300 |
commit | ec67aaa46dce26d671b46c94ac674ad0b67d044c (patch) | |
tree | e4819ea3c6b732dfb972c6507ec9f4c962e00129 /mm/cma_debug.c | |
parent | f1b4bd0676c2b3d4a023cf3f5d535e618f7e6eff (diff) | |
download | linux-ec67aaa46dce26d671b46c94ac674ad0b67d044c.tar.xz |
sysvipc/sem: mitigate semnum index against spectre v1
Both smatch and coverity are reporting potential issues with spectre
variant 1 with the 'semnum' index within the sma->sems array, ie:
ipc/sem.c:388 sem_lock() warn: potential spectre issue 'sma->sems'
ipc/sem.c:641 perform_atomic_semop_slow() warn: potential spectre issue 'sma->sems'
ipc/sem.c:721 perform_atomic_semop() warn: potential spectre issue 'sma->sems'
Avoid any possible speculation by using array_index_nospec() thus
ensuring the semnum value is bounded to [0, sma->sem_nsems). With the
exception of sem_lock() all of these are slowpaths.
Link: http://lkml.kernel.org/r/20180423171131.njs4rfm2yzyeg6do@linux-n805
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/cma_debug.c')
0 files changed, 0 insertions, 0 deletions