3ccc3167b0
While freeing indirect blocks we attach a journal head to the parent buffer head, free the blocks, then journal the parent. If the indirect block list is corrupted and points to the parent the journal head will be detached when the block is cleared, causing an OOPS. Check for that explicitly and handle it gracefully. This patch fixes the third case (image hdb.20000057.nullderef.gz) reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882. Immediately above the change, in the ext3_free_data function, we call ext3_clear_blocks to clear the indirect blocks in this parent block. If one of those blocks happens to actually be the parent block it will clear b_private / BH_JBD. I did the check at the end rather than earlier as it seemed more elegant. I don't think there should be much practical difference, although it is possible the FS may not be quite so badly corrupted if we did it the other way (and didn't clear the block at all). To be honest, I'm not convinced there aren't other similar failure modes lurking in this code, although I couldn't find any with a quick review. [akpm@linux-foundation.org: fix printk warning] Signed-off-by: Duane Griffin <duaneg@dghda.com> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| acl.c | ||
| acl.h | ||
| balloc.c | ||
| bitmap.c | ||
| dir.c | ||
| ext3_jbd.c | ||
| file.c | ||
| fsync.c | ||
| hash.c | ||
| ialloc.c | ||
| inode.c | ||
| ioctl.c | ||
| Makefile | ||
| namei.c | ||
| namei.h | ||
| resize.c | ||
| super.c | ||
| symlink.c | ||
| xattr_security.c | ||
| xattr_trusted.c | ||
| xattr_user.c | ||
| xattr.c | ||
| xattr.h | ||