mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-28 13:22:57 +00:00
Code Issues Releases Wiki Activity

ext2: Use kvmalloc() for group descriptor array

Browse source 
[ Upstream commit e7c7fbb9a8 ]

Array of group descriptor block buffers can get rather large. In theory
in can reach 1MB for perfectly valid filesystem and even more for
maliciously crafted ones. Use kvmalloc() to allocate the array to avoid
straining memory allocator with large order allocations unnecessarily.

Reported-by: syzbot+0f2f7e65a3007d39539f@syzkaller.appspotmail.com
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Jan Kara 2022-09-14 17:29:33 +02:00 committed by Greg Kroah-Hartman
parent 2bd74932d5
commit 993d6e991b
1 changed files with 3 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
fs/ext2/super.c
View file

@ -163,7 +163,7 @@ static void ext2_put_super (struct super_block * sb)
db_count = sbi->s_gdb_count;
for (i = 0; i < db_count; i++)
brelse(sbi->s_group_desc[i]);
kfree(sbi->s_group_desc);
kvfree(sbi->s_group_desc);
kfree(sbi->s_debts);
percpu_counter_destroy(&sbi->s_freeblocks_counter);
percpu_counter_destroy(&sbi->s_freeinodes_counter);
@ -1092,7 +1092,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
}
db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
EXT2_DESC_PER_BLOCK(sb);
sbi->s_group_desc = kmalloc_array(db_count,
sbi->s_group_desc = kvmalloc_array(db_count,
sizeof(struct buffer_head *),
GFP_KERNEL);
if (sbi->s_group_desc == NULL) {
@ -1218,7 +1218,7 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent)
for (i = 0; i < db_count; i++)
brelse(sbi->s_group_desc[i]);
failed_mount_group_desc:
kfree(sbi->s_group_desc);
kvfree(sbi->s_group_desc);
kfree(sbi->s_debts);
failed_mount:
brelse(bh);