Messages in this thread Patch in this message | | | Date | Tue, 30 Nov 2021 19:41:29 +0300 | From | Konstantin Komarov <> | Subject | [PATCH] fs/ntfs3: Fix NULL dereference in ntfs_update_mftmirr |
| |
We can get NULL pointer to struct super_block. This commit adds check for such situation. Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block") Thread: https://lore.kernel.org/lkml/20211125140816.GC3109@xsang-OptiPlex-9020/
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com> --- fs/ntfs3/fsntfs.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/fs/ntfs3/fsntfs.c b/fs/ntfs3/fsntfs.c index 4de9acb16968..38de8cb53183 100644 --- a/fs/ntfs3/fsntfs.c +++ b/fs/ntfs3/fsntfs.c @@ -831,14 +831,17 @@ int ntfs_update_mftmirr(struct ntfs_sb_info *sbi, int wait) { int err; struct super_block *sb = sbi->sb; - u32 blocksize = sb->s_blocksize; + u32 blocksize, bytes; sector_t block1, block2; - u32 bytes; - if (!(sbi->flags & NTFS_FLAGS_MFTMIRR)) + /* + * sb can be NULL here. In this case sbi->flags should be 0 too. + */ + if (!sb || !(sbi->flags & NTFS_FLAGS_MFTMIRR)) return 0; err = 0; + blocksize = sb->s_blocksize; bytes = sbi->mft.recs_mirr << sbi->record_bits; block1 = sbi->mft.lbo >> sb->s_blocksize_bits; block2 = sbi->mft.lbo2 >> sb->s_blocksize_bits; -- 2.33.1
| |