kernel/linux.git/fs/f2fs/segment.c, branch v5.15.210

f2fs: fix to do sanity check on dcc->discard_cmd_cnt conditionally

2026-06-19T11:33:39+00:00

[ Upstream commit 6af249c996f7d73a3435f9e577956fa259347d18 ] Syzbot reported a f2fs bug as below: ------------[ cut here ]------------ kernel BUG at fs/f2fs/segment.c:1900! Oops: invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 1 UID: 0 PID: 6527 Comm: syz.5.110 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:f2fs_issue_discard_timeout+0x59b/0x5a0 fs/f2fs/segment.c:1900 Code: d9 80 e1 07 80 c1 03 38 c1 0f 8c d6 fe ff ff 48 89 df e8 a8 5e fa fd e9 c9 fe ff ff e8 4e 46 94 fd 90 0f 0b e8 46 46 94 fd 90 <0f> 0b 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 RSP: 0018:ffffc9000494f940 EFLAGS: 00010283 RAX: ffffffff843009ca RBX: 0000000000000001 RCX: 0000000000080000 RDX: ffffc9001ca78000 RSI: 00000000000029f3 RDI: 00000000000029f4 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffed100893a431 R12: 1ffff1100893a430 R13: 1ffff1100c2b702c R14: dffffc0000000000 R15: ffff8880449d2160 FS: 00007ffa35fed6c0(0000) GS:ffff88812643d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f2b68634000 CR3: 0000000039f62000 CR4: 00000000003526f0 Call Trace: __f2fs_remount fs/f2fs/super.c:2960 [inline] f2fs_reconfigure+0x108a/0x1710 fs/f2fs/super.c:5443 reconfigure_super+0x227/0x8a0 fs/super.c:1080 do_remount fs/namespace.c:3391 [inline] path_mount+0xdc5/0x10e0 fs/namespace.c:4151 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4338 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffa37dbda0a The root cause is there will be race condition in between f2fs_ioc_fitrim() and f2fs_remount(): - f2fs_remount - f2fs_ioc_fitrim - f2fs_issue_discard_timeout - __issue_discard_cmd - __drop_discard_cmd - __wait_all_discard_cmd - f2fs_trim_fs - f2fs_write_checkpoint - f2fs_clear_prefree_segments - f2fs_issue_discard - __issue_discard_async - __queue_discard_cmd - __update_discard_tree_range - __insert_discard_cmd - __create_discard_cmd : atomic_inc(&dcc->discard_cmd_cnt); - sanity check on dcc->discard_cmd_cnt (expect discard_cmd_cnt to be zero) This will only happen when fitrim races w/ remount rw, if we remount to readonly filesystem, remount will wait until mnt_pcp.mnt_writers to zero, that means fitrim is not in process at that time. Cc: stable@kernel.org Fixes: 2482c4325dfe ("f2fs: detect bug_on in f2fs_wait_discard_bios") Reported-by: syzbot+62538b67389ee582837a@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-f2fs-devel/69b07d7c.050a0220.8df7.09a1.GAE@google.com Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim [ Different function signatures ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

f2fs: check curseg->inited before write_sum_page in change_curseg

2024-12-14T18:51:05+00:00

[ Upstream commit 43563069e1c1df417d2eed6eca8a22fc6b04691d ] In the __f2fs_init_atgc_curseg->get_atssr_segment calling, curseg->segno is NULL_SEGNO, indicating that there is no summary block that needs to be written. Fixes: 093749e296e2 ("f2fs: support age threshold based garbage collection") Signed-off-by: Yongpeng Yang Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: remove the unused flush argument to change_curseg

2024-12-14T18:51:05+00:00

[ Upstream commit 5bcd655fffaec24e849bda1207446f5cc821713e ] Signed-off-by: Christoph Hellwig Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: 43563069e1c1 ("f2fs: check curseg->inited before write_sum_page in change_curseg") Signed-off-by: Sasha Levin

f2fs: open code allocate_segment_by_default

2024-12-14T18:51:05+00:00

[ Upstream commit 8442d94b8ac8d5d8300725a9ffa9def526b71170 ] allocate_segment_by_default has just two callers, which use very different code pathes inside it based on the force paramter. Just open code the logic in the two callers using a new helper to decided if a new segment should be allocated. Signed-off-by: Christoph Hellwig Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: 43563069e1c1 ("f2fs: check curseg->inited before write_sum_page in change_curseg") Signed-off-by: Sasha Levin

f2fs: remove struct segment_allocation default_salloc_ops

2024-12-14T18:51:05+00:00

[ Upstream commit 1c8a8ec0a0e9a1176022a35c4daf04fe1594d270 ] There is only single instance of these ops, so remove the indirection and call allocate_segment_by_default directly. Signed-off-by: Christoph Hellwig Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: 43563069e1c1 ("f2fs: check curseg->inited before write_sum_page in change_curseg") Signed-off-by: Sasha Levin

f2fs: fix the wrong f2fs_bug_on condition in f2fs_do_replace_block

2024-12-14T18:51:05+00:00

[ Upstream commit c3af1f13476ec23fd99c98d060a89be28c1e8871 ] This f2fs_bug_on was introduced by commit 2c1905042c8c ("f2fs: check segment type in __f2fs_replace_block") when there were only 6 curseg types. After commit d0b9e42ab615 ("f2fs: introduce inmem curseg") was introduced, the condition should be changed to checking curseg->seg_type. Fixes: d0b9e42ab615 ("f2fs: introduce inmem curseg") Signed-off-by: LongPing Wei Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix to do sanity check in update_sit_entry

2024-09-04T11:23:26+00:00

[ Upstream commit 36959d18c3cf09b3c12157c6950e18652067de77 ] If GET_SEGNO return NULL_SEGNO for some unecpected case, update_sit_entry will access invalid memory address, cause system crash. It is better to do sanity check about GET_SEGNO just like update_segment_mtime & locate_dirty_segment. Also remove some redundant judgment code. Signed-off-by: Zhiguo Niu Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin

f2fs: fix typos in comments

2024-06-16T11:39:36+00:00

[ Upstream commit 146949defda868378992171b9e42318b06fcd482 ] This patch is to fix typos in f2fs files. Signed-off-by: Jinyoung Choi Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: 278a6253a673 ("f2fs: fix to relocate check condition in f2fs_fallocate()") Signed-off-by: Sasha Levin

f2fs: reduce stack memory cost by using bitfield in struct f2fs_io_info

2024-03-26T22:21:32+00:00

[ Upstream commit 2eae077e6e46f9046d383631145750e043820dce ] This patch tries to use bitfield in struct f2fs_io_info to improve memory usage. struct f2fs_io_info { ... unsigned int need_lock:8; /* indicate we need to lock cp_rwsem */ unsigned int version:8; /* version of the node */ unsigned int submitted:1; /* indicate IO submission */ unsigned int in_list:1; /* indicate fio is in io_list */ unsigned int is_por:1; /* indicate IO is from recovery or not */ unsigned int retry:1; /* need to reallocate block address */ unsigned int encrypted:1; /* indicate file is encrypted */ unsigned int post_read:1; /* require post read */ ... }; After this patch, size of struct f2fs_io_info reduces from 136 to 120. [Nathan: fix a compile warning (single-bit-bitfield-constant-conversion)] Signed-off-by: Nathan Chancellor Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: fd244524c2cf ("f2fs: compress: fix to cover normal cluster write with cp_rwsem") Signed-off-by: Sasha Levin

f2fs: invalidate meta pages only for post_read required inode

2024-03-26T22:21:32+00:00

[ Upstream commit 0d5b9d8156396bbe1c982708b38ab9e188c45ec9 ] After commit e3b49ea36802 ("f2fs: invalidate META_MAPPING before IPU/DIO write"), invalidate_mapping_pages() will be called to avoid race condition in between IPU/DIO and readahead for GC. However, readahead flow is only used for post_read required inode, so this patch adds check condition to avoids unnecessary page cache invalidating for non-post_read inode. Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Stable-dep-of: fd244524c2cf ("f2fs: compress: fix to cover normal cluster write with cp_rwsem") Signed-off-by: Sasha Levin