dentry_string_cmp() performs the word-at-a-time reads from 'cs' and may
read slightly more than it was requested in kmallac(). Normally this
would make KASAN to report out-of-bounds access, but this was workarounded
by commit df4c0e36f1b1 ("fs: dcache: manually unpoison dname after
allocation to shut up kasan's reports").This workaround is not perfect, since it allows out-of-bounds access to dentry's name for all the code, not just in dentry_string_cmp(). So it would be better to use read_word_at_a_time() instead and revert commit df4c0e36f1b1. Signed-off-by: Andrey Ryabinin <[email protected]> --- fs/dcache.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/dcache.c b/fs/dcache.c index c99812fd54b3..195999c8d1b4 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -193,7 +193,7 @@ static inline int dentry_string_cmp(const unsigned char *cs, const unsigned char unsigned long a,b,mask; for (;;) { - a = *(unsigned long *)cs; + a = read_word_at_a_time(cs); b = load_unaligned_zeropad(ct); if (tcount < sizeof(unsigned long)) break; -- 2.13.6
