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Subject[PATCH] ext2/super: Fix a possible sleep-in-atomic bug in parse_options
Date
The kernel may sleep under a spinlock, and the function call path is:
ext2_remount
parse_options
match_int
match_number (lib/parser.c)
kmalloc(GFP_KERNEL) --> may sleep

To fix it, GFP_KERNEL is replaced with GFP_ATOMIC.
This bug is found by my static analysis tool and my code review.

Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
---
lib/parser.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/parser.c b/lib/parser.c
index 3278958..bc6e2ce 100644
--- a/lib/parser.c
+++ b/lib/parser.c
@@ -133,7 +133,7 @@ static int match_number(substring_t *s, int *result, int base)
long val;
size_t len = s->to - s->from;

- buf = kmalloc(len + 1, GFP_KERNEL);
+ buf = kmalloc(len + 1, GFP_ATOMIC);
if (!buf)
return -ENOMEM;
memcpy(buf, s->from, len);
--
1.7.9.5

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