forked from Minki/linux
54d7185642
If extent cache is disable, we will encounter oops when triggering direct IO as below: BUG: unable to handle kernel NULL pointer dereference at 0000000c IP: [<f0b9c61e>] f2fs_drop_largest_extent+0xe/0x30 [f2fs] *pdpt = 000000002bb9a001 *pde = 0000000000000000 Oops: 0000 [#1] SMP Modules linked in: f2fs(O) fuse bnep rfcomm bluetooth nfsd dm_crypt nfs_acl auth_rpcgss oid_registry nfs binfmt_misc fscache lockd sunrpc grace snd_intel8x0 snd_ac97_codec ac97_bus snd_pcm snd_seq_midi snd_rawmidi snd_seq_midi_event snd_seq snd_timer snd_seq_device snd soundcore joydev psmouse hid_generic i2c_piix4 serio_raw ppdev mac_hid parport_pc lp parport ext4 jbd2 mbcache usbhid hid e1000 CPU: 3 PID: 3608 Comm: dd Tainted: G O 4.2.0-rc4 #12 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 task: ef161600 ti: ebd5e000 task.ti: ebd5e000 EIP: 0060:[<f0b9c61e>] EFLAGS: 00010202 CPU: 3 EIP is at f2fs_drop_largest_extent+0xe/0x30 [f2fs] EAX: 00000000 EBX: ddebc000 ECX: 00000000 EDX: 00000000 ESI: ebd5fdf8 EDI: 00000000 EBP: ebd5fd58 ESP: ebd5fd58 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 80050033 CR2: 0000000c CR3: 2c24ee40 CR4: 000006f0 Stack: ebd5fda4 f0b8c005 00000000 00000001 00000000 f0b8c430 c816cd68 ddebc000 ddebc088 00001000 00000555 00000555 ffffffff c160bb00 00055501 00000000 00000000 00000100 00000000 ebd5fe20 f0b8c430 00000046 ef161600 00001000 Call Trace: [<f0b8c005>] __allocate_data_block+0x1a5/0x260 [f2fs] [<f0b8c430>] ? f2fs_direct_IO+0x370/0x440 [f2fs] [<c160bb00>] ? down_read+0x30/0x50 [<f0b8c430>] f2fs_direct_IO+0x370/0x440 [f2fs] [<c113e115>] generic_file_direct_write+0xa5/0x260 [<c10b53f8>] ? current_fs_time+0x18/0x50 [<c113e38b>] __generic_file_write_iter+0xbb/0x210 [<c113e50f>] ? generic_file_write_iter+0x2f/0x320 [<c113e63c>] generic_file_write_iter+0x15c/0x320 [<f0b77f29>] f2fs_file_write_iter+0x39/0x80 [f2fs] [<c11984d9>] __vfs_write+0xa9/0xe0 [<c1199227>] vfs_write+0x97/0x180 [<c119955b>] SyS_write+0x5b/0xd0 [<c160dcd0>] sysenter_do_call+0x12/0x12 Code: 10 8b 50 1c 89 53 14 eb ca 8d 74 26 00 85 f6 74 86 eb a6 0f 0b 90 8d b4 26 00 00 00 00 55 89 e5 3e 8d 74 26 00 8b 80 d4 02 00 00 <8b> 48 0c 39 d1 77 0e 03 48 14 39 ca 73 07 c7 40 14 00 00 00 00 EIP: [<f0b9c61e>] f2fs_drop_largest_extent+0xe/0x30 [f2fs] SS:ESP 0068:ebd5fd58 CR2: 000000000000000c ---[ end trace a38c07026a1afffd ]--- This is because when extent cache is disable, extent_tree pointer in struct f2fs_inode_info should be NULL, but in f2fs_drop_largest_extent we access this NULL pointer directly without checking state of extent cache, then, the oops occurs. Let's fix it by checking state of extent cache before accessing. Signed-off-by: Chao Yu <chao2.yu@samsung.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> |
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| .. | ||
| acl.c | ||
| acl.h | ||
| checkpoint.c | ||
| crypto_fname.c | ||
| crypto_key.c | ||
| crypto_policy.c | ||
| crypto.c | ||
| data.c | ||
| debug.c | ||
| dir.c | ||
| extent_cache.c | ||
| f2fs_crypto.h | ||
| f2fs.h | ||
| file.c | ||
| gc.c | ||
| gc.h | ||
| hash.c | ||
| inline.c | ||
| inode.c | ||
| Kconfig | ||
| Makefile | ||
| namei.c | ||
| node.c | ||
| node.h | ||
| recovery.c | ||
| segment.c | ||
| segment.h | ||
| shrinker.c | ||
| super.c | ||
| trace.c | ||
| trace.h | ||
| xattr.c | ||
| xattr.h | ||