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| author | Gaosheng Cui <cuigaosheng1@huawei.com> | 2022-10-31 13:58:33 +0800 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2022-12-08 21:49:23 -0500 |
| commit | 3bf678a0f9c017c9ba7c581541dbc8453452a7ae (patch) | |
| tree | a0c954f2e134e3ebb6b19d84cb86d192553b2ad9 /fs/ext4/ext4.h | |
| parent | 991ed014de0840c5dc405b679168924afb2952ac (diff) | |
| download | lwn-3bf678a0f9c017c9ba7c581541dbc8453452a7ae.tar.gz lwn-3bf678a0f9c017c9ba7c581541dbc8453452a7ae.zip | |
ext4: fix undefined behavior in bit shift for ext4_check_flag_values
Shifting signed 32-bit value by 31 bits is undefined, so changing
significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in fs/ext4/ext4.h:591:2
left shift of 1 by 31 places cannot be represented in type 'int'
Call Trace:
<TASK>
dump_stack_lvl+0x7d/0xa5
dump_stack+0x15/0x1b
ubsan_epilogue+0xe/0x4e
__ubsan_handle_shift_out_of_bounds+0x1e7/0x20c
ext4_init_fs+0x5a/0x277
do_one_initcall+0x76/0x430
kernel_init_freeable+0x3b3/0x422
kernel_init+0x24/0x1e0
ret_from_fork+0x1f/0x30
</TASK>
Fixes: 9a4c80194713 ("ext4: ensure Inode flags consistency are checked at build time")
Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Link: https://lore.kernel.org/r/20221031055833.3966222-1-cuigaosheng1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Diffstat (limited to 'fs/ext4/ext4.h')
| -rw-r--r-- | fs/ext4/ext4.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 2b574b143bde..3afdd99bb214 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -558,7 +558,7 @@ enum { * * It's not paranoia if the Murphy's Law really *is* out to get you. :-) */ -#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG)) +#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1U << EXT4_INODE_##FLAG)) #define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG)) static inline void ext4_check_flag_values(void) |