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| author | Michael Schmitz <schmitzmic@gmail.com> | 2017-04-30 19:49:21 +1200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-04-13 19:52:14 +0200 |
| commit | d3d9fa5e0499faf0f31b6555aa2fe9d52d1123ad (patch) | |
| tree | 0113994d7f00bef9b37896165162116e209d30da /fs/ext4/file.c | |
| parent | aef4c08f785c0764d5302b88e9385146519bfc15 (diff) | |
fix race in drivers/char/random.c:get_reg()
[ Upstream commit 9dfa7bba35ac08a63565d58c454dccb7e1bb0a08 ]
get_reg() can be reentered on architectures with prioritized interrupts
(m68k in this case), causing f->reg_index to be incremented after the
range check. Out of bounds memory access past the pt_regs struct results.
This will go mostly undetected unless access is beyond end of memory.
Prevent the race by disabling interrupts in get_reg().
Tested on m68k (Atari Falcon, and ARAnyM emulator).
Kudos to Geert Uytterhoeven for helping to trace this race.
Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/ext4/file.c')
0 files changed, 0 insertions, 0 deletions