The patch titled Subject: nilfs2: fix NULL pointer dereference in nilfs_load_super_block() has been added to the -mm tree. Its filename is nilfs2-fix-null-pointer-dereference-in-nilfs_load_super_block.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxxxxxx> Subject: nilfs2: fix NULL pointer dereference in nilfs_load_super_block() According to the report from Slicky Devil, nilfs caused kernel oops at nilfs_load_super_block function during mount after he shrank the partition without resizing the filesystem: BUG: unable to handle kernel NULL pointer dereference at 00000048 IP: [<d0d7a08e>] nilfs_load_super_block+0x17e/0x280 [nilfs2] *pde = 00000000 Oops: 0000 [#1] PREEMPT SMP ... Call Trace: [<d0d7a87b>] init_nilfs+0x4b/0x2e0 [nilfs2] [<d0d6f707>] nilfs_mount+0x447/0x5b0 [nilfs2] [<c01f33a4>] ? pcpu_alloc+0x714/0x810 [<c02d2add>] ? ida_get_new_above+0x1ad/0x230 [<c02d2add>] ? ida_get_new_above+0x1ad/0x230 [<c0226636>] mount_fs+0x36/0x180 [<c01f34af>] ? __alloc_percpu+0xf/0x20 [<c023d961>] vfs_kern_mount+0x51/0xa0 [<c023ddae>] do_kern_mount+0x3e/0xe0 [<c023f189>] do_mount+0x169/0x700 [<c01eeb29>] ? strndup_user+0x49/0x70 [<c023fa9b>] sys_mount+0x6b/0xa0 [<c04abd1f>] sysenter_do_call+0x12/0x28 Code: 53 18 8b 43 20 89 4b 18 8b 4b 24 89 53 1c 89 43 24 89 4b 20 8b 43 20 c7 43 2c 00 00 00 00 23 75 e8 8b 50 68 89 53 28 8b 54 b3 20 <8b> 72 48 8b 7a 4c 8b 55 08 89 b3 84 00 00 00 89 bb 88 00 00 00 EIP: [<d0d7a08e>] nilfs_load_super_block+0x17e/0x280 [nilfs2] SS:ESP 0068:ca9bbdcc CR2: 0000000000000048 This turned out due to a defect in an error path which runs if the calculated location of the secondary super block was invalid. This patch fixes it and eliminates the reported oops. Reported-by: Slicky Devil <slicky.dvl@xxxxxxxxx> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxxxxxx> Tested-by: Slicky Devil <slicky.dvl@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> [2.6.30+] Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/nilfs2/the_nilfs.c | 1 + 1 file changed, 1 insertion(+) diff -puN fs/nilfs2/the_nilfs.c~nilfs2-fix-null-pointer-dereference-in-nilfs_load_super_block fs/nilfs2/the_nilfs.c --- a/fs/nilfs2/the_nilfs.c~nilfs2-fix-null-pointer-dereference-in-nilfs_load_super_block +++ a/fs/nilfs2/the_nilfs.c @@ -521,6 +521,7 @@ static int nilfs_load_super_block(struct brelse(sbh[1]); sbh[1] = NULL; sbp[1] = NULL; + valid[1] = 0; swp = 0; } if (!valid[swp]) { _ Subject: Subject: nilfs2: fix NULL pointer dereference in nilfs_load_super_block() Patches currently in -mm which might be from konishi.ryusuke@xxxxxxxxxxxxx are nilfs2-clamp-ns_r_segments_percentage-to.patch nilfs2-fix-null-pointer-dereference-in-nilfs_load_super_block.patch linux-next.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html