Commit b6654142 authored by Ye Bin's avatar Ye Bin Committed by Theodore Ts'o
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ext4: fix potential uninitialized access to retval in kmmpd 



if (!ext4_has_feature_mmp(sb)) then retval can be unitialized before
we jump to the wait_to_exit label.

Fixes: 61bb4a1c ("ext4: fix possible UAF when remounting r/o a mmp-protected file system")
Signed-off-by: default avatarYe Bin <yebin10@huawei.com>
Link: https://lore.kernel.org/r/20210713022728.2533770-1-yebin10@huawei.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 2734d6c1

fs/ext4/mmp.c

+1 −1
Original line number Diff line number Diff line
@@ -138,7 +138,7 @@ static int kmmpd(void *data) 
	unsigned mmp_check_interval;

	unsigned long last_update_time;

	unsigned long diff;

	int retval;

	int retval = 0;



	mmp_block = le64_to_cpu(es->s_mmp_block);

	mmp = (struct mmp_struct *)(bh->b_data);