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FAILED: patch "[PATCH] f2fs: fix to do sanity check on f2fs_get_node_folio_ra()" failed to apply to 6.18-stable tree

PATCH New [email protected] 2 participants 6 messages Jul 2 – Jul 4

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Stable branch F2FS file system
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[email protected]

author maintainer
#0 lore raw

The patch below does not apply to the 6.18-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.18.y
git checkout FETCH_HEAD
git cherry-pick -x 8712353ed80f87271d732297567dcdbe4b84e8c7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2026070234-outdated-refutable-f834@gregkh' --subject-prefix 'PATCH 6.18.y' 'HEAD^..'

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8712353ed80f87271d732297567dcdbe4b84e8c7 Mon Sep 17 00:00:00 2001
From: Chao Yu <[email protected]>
Date: Fri, 22 May 2026 15:53:29 +0800
Subject: [PATCH] f2fs: fix to do sanity check on f2fs_get_node_folio_ra()

kernel BUG at fs/f2fs/file.c:845!

Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5336 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:f2fs_do_truncate_blocks+0x1115/0x1140 fs/f2fs/file.c:845
Code: fc fc 90 0f 0b e8 8b 9d 9a fd 90 0f 0b e8 83 9d 9a fd 48 89 df 48 c7 c6 60 d1 1a 8c e8 54 f1 fc fc 90 0f 0b e8 6c 9d 9a fd 90 <0f> 0b e8 64 9d 9a fd 90 0f 0b 90 e9 93 fd ff ff e8 56 9d 9a fd 90
RSP: 0018:ffffc9000e4474c0 EFLAGS: 00010283
RAX: ffffffff842b1d34 RBX: 0000000000000003 RCX: 0000000000100000
RDX: ffffc9000f03a000 RSI: 0000000000035503 RDI: 0000000000035504
RBP: ffffc9000e447608 R08: ffff8880123b0000 R09: 0000000000000002
R10: 00000000fffffffe R11: 0000000000000002 R12: 0000000000000001
R13: 0000000000000000 R14: 1ffff92001c88ea0 R15: 00000000ffff039c
FS:  00007f7e02ee36c0(0000) GS:ffff88808c887000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff0305c4000 CR3: 0000000012d4c000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 f2fs_truncate_blocks+0x10a/0x300 fs/f2fs/file.c:882
 f2fs_truncate+0x471/0x7c0 fs/f2fs/file.c:940
 f2fs_evict_inode+0xa3f/0x1ac0 fs/f2fs/inode.c:907
 evict+0x61e/0xb10 fs/inode.c:841
 f2fs_fill_super+0x5f43/0x78f0 fs/f2fs/super.c:5224
 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
 vfs_get_tree+0x92/0x2a0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x341/0xd30 fs/namespace.c:3834
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
	count = ADDRS_PER_PAGE(dn.node_folio, inode);

	count -= dn.ofs_in_node;
	f2fs_bug_on(sbi, count < 0);

The fuzz test will trigger above bug_on in f2fs.

The root cause should be: in the corrupted inode, there is a direct node which has the same ino and nid in its footer, so in f2fs_do_truncate_blocks(), after f2fs_get_dnode_of_data() finds such dnode:
1) ADDRS_PER_PAGE(dn.node_folio, inode) will return 923
2) once dn.ofs_in_node points to addr[923, 1017]
Then it will trigger the system panic.

Let's introduce NODE_TYPE_NON_IXNODE to indicate current node should not be an inode or xattr node, and then use it in below path to detect inconsistent node chain in inode mapping table:

- f2fs_do_truncate_blocks
- f2fs_get_dnode_of_data
- f2fs_get_node_folio_ra
- __get_node_folio
- f2fs_sanity_check_node_footer
- case NODE_TYPE_NON_IXNODE -> check whether it is inode|xnode

Cc [email protected]
Reported-by [email protected]
Closes https://lore.kernel.org/all/[email protected] open here
Signed-off-by Chao Yu <[email protected]>
Signed-off-by Jaegeuk Kim <[email protected]>
fs/f2fs/f2fs.h +1 -0
index 9f24287de4c3..086bc5243979 100644
@@ -1592,6 +1592,7 @@ enum node_type {
 	NODE_TYPE_INODE,
 	NODE_TYPE_XATTR,
 	NODE_TYPE_NON_INODE,
+	NODE_TYPE_NON_IXNODE,	/* non inode and xnode */
 };
 
 /* a threshold of maximum elapsed time in critical region to print tracepoint */
fs/f2fs/node.c +5 -1
index cd5a394f6111..38917e4a7319 100644
@@ -1548,6 +1548,10 @@ int f2fs_sanity_check_node_footer(struct f2fs_sb_info *sbi,
 		if (is_inode)
 			goto out_err;
 		break;
+	case NODE_TYPE_NON_IXNODE:
+		if (is_inode || is_xnode)
+			goto out_err;
+		break;
 	default:
 		break;
 	}

@@ -1643,7 +1647,7 @@ static struct folio *f2fs_get_node_folio_ra(struct folio *parent, int start)
 	struct f2fs_sb_info *sbi = F2FS_F_SB(parent);
 	nid_t nid = get_nid(parent, start, false);
 
-	return __get_node_folio(sbi, nid, parent, start, NODE_TYPE_REGULAR);
+	return __get_node_folio(sbi, nid, parent, start, NODE_TYPE_NON_IXNODE);
 }
 
 static void flush_inline_data(struct f2fs_sb_info *sbi, nid_t ino)
maintainer
#1 lore raw

PATCH 1/5 f2fs: use memalloc_retry_wait() as much as possible

From: Chao Yu <[email protected]>

[ Upstream commit 30a8496694f1a93328e5d7f19206380346918b5a ]

memalloc_retry_wait() is recommended in memory allocation retry logic, use it as much as possible.

Signed-off-by Chao Yu <[email protected]>
Signed-off-by Jaegeuk Kim <[email protected]>

Stable-dep-of: 8712353ed80f ("f2fs: fix to do sanity check on f2fs_get_node_folio_ra()")

Signed-off-by Sasha Levin <[email protected]>
---
 fs/f2fs/segment.c | 2 +-
 fs/f2fs/super.c   | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)
fs/f2fs/segment.c +1 -1
index a7cf8627d88811..4739decfc88863 100644
@@ -234,7 +234,7 @@ static int __replace_atomic_write_block(struct inode *inode, pgoff_t index,
 	err = f2fs_get_dnode_of_data(&dn, index, ALLOC_NODE);
 	if (err) {
 		if (err == -ENOMEM) {
-			f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+			memalloc_retry_wait(GFP_NOFS);
 			goto retry;
 		}
 		return err;
fs/f2fs/super.c +1 -1
index 9154f702e1706a..fc4a2e915ca09a 100644
@@ -3128,7 +3128,7 @@ static ssize_t f2fs_quota_write(struct super_block *sb, int type,
 							&folio, &fsdata);
 		if (unlikely(err)) {
 			if (err == -ENOMEM) {
-				f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+				memalloc_retry_wait(GFP_NOFS);
 				goto retry;
 			}
 			set_sbi_flag(F2FS_SB(sb), SBI_QUOTA_NEED_REPAIR);
Signature · 1 line
2.53.0
maintainer
#2 lore raw

PATCH 2/5 f2fs: introduce f2fs_schedule_timeout()

From: Chao Yu <[email protected]>

[ Upstream commit 76e780d88c771921ea643fb8a6c8d0b08c17cb7b ]

In f2fs retry logic, we will call f2fs_io_schedule_timeout() to sleep as uninterruptible state (waiting for IO) for a while, however, in several paths below, we are not blocked by IO:
- f2fs_write_single_data_page() return -EAGAIN due to racing on cp_rwsem.
- f2fs_flush_device_cache() failed to submit preflush command.
- __issue_discard_cmd_range() sleeps periodically in between two in batch discard submissions.

So, in order to reveal state of task more accurate, let's introduce f2fs_schedule_timeout() and call it in above paths in where we are waiting for non-IO reasons.

Then we can get real reason of uninterruptible sleep for a thread in tracepoint, perfetto, etc.

Signed-off-by Chao Yu <[email protected]>
Signed-off-by Jaegeuk Kim <[email protected]>

Stable-dep-of: 8712353ed80f ("f2fs: fix to do sanity check on f2fs_get_node_folio_ra()")

Signed-off-by Sasha Levin <[email protected]>
---
 fs/f2fs/checkpoint.c |  4 ++--
 fs/f2fs/compress.c   |  4 ++--
 fs/f2fs/data.c       |  4 ++--
 fs/f2fs/f2fs.h       | 22 +++++++++++++++-------
 fs/f2fs/segment.c    |  4 ++--
 fs/f2fs/super.c      |  2 +-
 6 files changed, 24 insertions(+), 16 deletions(-)
fs/f2fs/checkpoint.c +2 -2
index bbe07e3a6c75ac..4c401b5b29336b 100644
@@ -1318,7 +1318,7 @@ void f2fs_wait_on_all_pages(struct f2fs_sb_info *sbi, int type)
 			f2fs_submit_merged_write(sbi, DATA);
 
 		prepare_to_wait(&sbi->cp_wait, &wait, TASK_UNINTERRUPTIBLE);
-		io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+		io_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
 	}
 	finish_wait(&sbi->cp_wait, &wait);
 }

@@ -1974,7 +1974,7 @@ void f2fs_flush_ckpt_thread(struct f2fs_sb_info *sbi)
 
 	/* Let's wait for the previous dispatched checkpoint. */
 	while (atomic_read(&cprc->queued_ckpt))
-		io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+		io_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
 }
 
 void f2fs_init_ckpt_req_control(struct f2fs_sb_info *sbi)
fs/f2fs/compress.c +2 -2
index ae36bb1f93519d..0399db98fccfc3 100644
@@ -1057,7 +1057,7 @@ static void cancel_cluster_writeback(struct compress_ctx *cc,
 		f2fs_submit_merged_write(F2FS_I_SB(cc->inode), DATA);
 		while (atomic_read(&cic->pending_pages) !=
 					(cc->valid_nr_cpages - submitted + 1))
-			f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+			f2fs_io_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
 	}
 
 	/* Cancel writeback and stay locked. */

@@ -1582,7 +1582,7 @@ static int f2fs_write_raw_pages(struct compress_ctx *cc,
 				 */
 				if (IS_NOQUOTA(cc->inode))
 					goto out;
-				f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+				f2fs_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
 				goto retry_write;
 			}
 			goto out;
fs/f2fs/data.c +2 -2
index f468cba89f303b..1408c5bce358f6 100644
@@ -3185,8 +3185,8 @@ static int f2fs_write_cache_pages(struct address_space *mapping,
 				} else if (ret == -EAGAIN) {
 					ret = 0;
 					if (wbc->sync_mode == WB_SYNC_ALL) {
-						f2fs_io_schedule_timeout(
-							DEFAULT_IO_TIMEOUT);
+						f2fs_schedule_timeout(
+							DEFAULT_SCHEDULE_TIMEOUT);
 						goto retry_write;
 					}
 					goto next;
fs/f2fs/f2fs.h +15 -7
index a77858bd38779f..ef1a3861b0bf5c 100644
@@ -665,8 +665,8 @@ enum {
 
 #define DEFAULT_RETRY_IO_COUNT	8	/* maximum retry read IO or flush count */
 
-/* congestion wait timeout value, default: 20ms */
-#define	DEFAULT_IO_TIMEOUT	(msecs_to_jiffies(20))
+/* IO/non-IO congestion wait timeout value, default: 20ms */
+#define	DEFAULT_SCHEDULE_TIMEOUT	(msecs_to_jiffies(20))
 
 /* timeout value injected, default: 1000ms */
 #define DEFAULT_FAULT_TIMEOUT	(msecs_to_jiffies(1000))

@@ -4939,22 +4939,30 @@ static inline bool f2fs_block_unit_discard(struct f2fs_sb_info *sbi)
 	return F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_BLOCK;
 }
 
-static inline void f2fs_io_schedule_timeout(long timeout)
+static inline void __f2fs_schedule_timeout(long timeout, bool io)
 {
 	set_current_state(TASK_UNINTERRUPTIBLE);
-	io_schedule_timeout(timeout);
+	if (io)
+		io_schedule_timeout(timeout);
+	else
+		schedule_timeout(timeout);
 }
 
+#define f2fs_io_schedule_timeout(timeout)		\
+			__f2fs_schedule_timeout(timeout, true)
+#define f2fs_schedule_timeout(timeout)			\
+			__f2fs_schedule_timeout(timeout, false)
+
 static inline void f2fs_io_schedule_timeout_killable(long timeout)
 {
 	while (timeout) {
 		if (fatal_signal_pending(current))
 			return;
 		set_current_state(TASK_UNINTERRUPTIBLE);
-		io_schedule_timeout(DEFAULT_IO_TIMEOUT);
-		if (timeout <= DEFAULT_IO_TIMEOUT)
+		io_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
+		if (timeout <= DEFAULT_SCHEDULE_TIMEOUT)
 			return;
-		timeout -= DEFAULT_IO_TIMEOUT;
+		timeout -= DEFAULT_SCHEDULE_TIMEOUT;
 	}
 }
fs/f2fs/segment.c +2 -2
index 4739decfc88863..3a3e751ec9f766 100644
@@ -750,7 +750,7 @@ int f2fs_flush_device_cache(struct f2fs_sb_info *sbi)
 		do {
 			ret = __submit_flush_wait(sbi, FDEV(i).bdev);
 			if (ret)
-				f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+				f2fs_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
 		} while (ret && --count);
 
 		if (ret) {

@@ -3472,7 +3472,7 @@ static unsigned int __issue_discard_cmd_range(struct f2fs_sb_info *sbi,
 			blk_finish_plug(&plug);
 			mutex_unlock(&dcc->cmd_lock);
 			trimmed += __wait_all_discard_cmd(sbi, NULL);
-			f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+			f2fs_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
 			goto next;
 		}
 skip:
fs/f2fs/super.c +1 -1
index fc4a2e915ca09a..f6b75ce11d1c1a 100644
@@ -2656,7 +2656,7 @@ static int f2fs_enable_checkpoint(struct f2fs_sb_info *sbi)
 	/* we should flush all the data to keep data consistency */
 	while (get_pages(sbi, F2FS_DIRTY_DATA)) {
 		writeback_inodes_sb_nr(sbi->sb, nr_pages, WB_REASON_SYNC);
-		f2fs_io_schedule_timeout(DEFAULT_IO_TIMEOUT);
+		f2fs_io_schedule_timeout(DEFAULT_SCHEDULE_TIMEOUT);
 
 		if (f2fs_time_over(sbi, ENABLE_TIME))
 			break;
Signature · 1 line
2.53.0
maintainer
#3 lore raw

PATCH 3/5 f2fs: optimize trace_f2fs_write_checkpoint with enums

In reply to Sasha Levin

From: YH Lin <[email protected]>

[ Upstream commit 8d1cb17aca466b361cca17834b8bb1cf3e3d1818 ]

This patch optimizes the tracepoint by replacing these hardcoded strings with a new enumeration f2fs_cp_phase.

1.Defines enum f2fs_cp_phase with values for each checkpoint phase. 2.Updates trace_f2fs_write_checkpoint to accept a u16 phase argument instead of a string pointer.
3.Uses __print_symbolic in TP_printk to convert the enum values back to their corresponding strings for human-readable trace output.

This change reduces the storage overhead for each trace event by replacing a variable-length string with a 2-byte integer, while maintaining the same readable output in ftrace.

Signed-off-by YH Lin <[email protected]>
Reviewed-by Chao Yu <[email protected]>
Signed-off-by Jaegeuk Kim <[email protected]>

Stable-dep-of: 8712353ed80f ("f2fs: fix to do sanity check on f2fs_get_node_folio_ra()")

Signed-off-by Sasha Levin <[email protected]>
---
 fs/f2fs/checkpoint.c        |  6 +++---
 fs/f2fs/f2fs.h              |  6 ++++++
 include/trace/events/f2fs.h | 19 ++++++++++++++-----
 3 files changed, 23 insertions(+), 8 deletions(-)
fs/f2fs/checkpoint.c +3 -3
index 4c401b5b29336b..300664269eb624 100644
@@ -1673,7 +1673,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 		goto out;
 	}
 
-	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "start block_ops");
+	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, CP_PHASE_START_BLOCK_OPS);
 
 	err = block_operations(sbi);
 	if (err)

@@ -1681,7 +1681,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	stat_cp_time(cpc, CP_TIME_OP_LOCK);
 
-	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish block_ops");
+	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, CP_PHASE_FINISH_BLOCK_OPS);
 
 	f2fs_flush_merged_writes(sbi);
 

@@ -1747,7 +1747,7 @@ int f2fs_write_checkpoint(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 
 	/* update CP_TIME to trigger checkpoint periodically */
 	f2fs_update_time(sbi, CP_TIME);
-	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, "finish checkpoint");
+	trace_f2fs_write_checkpoint(sbi->sb, cpc->reason, CP_PHASE_FINISH_CHECKPOINT);
 out:
 	if (cpc->reason != CP_RESIZE)
 		f2fs_up_write(&sbi->cp_global_sem);
fs/f2fs/f2fs.h +6 -0
index ef1a3861b0bf5c..31252fb1b06bd1 100644
@@ -319,6 +319,12 @@ struct cp_control {
 	struct cp_stats stats;
 };
 
+enum f2fs_cp_phase {
+	CP_PHASE_START_BLOCK_OPS,
+	CP_PHASE_FINISH_BLOCK_OPS,
+	CP_PHASE_FINISH_CHECKPOINT,
+};
+
 /*
  * indicate meta/data type
  */
include/trace/events/f2fs.h +14 -5
index edbbd869078f06..abf5bc7dad9a0b 100644
@@ -50,6 +50,9 @@ TRACE_DEFINE_ENUM(CP_PAUSE);
 TRACE_DEFINE_ENUM(CP_RESIZE);
 TRACE_DEFINE_ENUM(EX_READ);
 TRACE_DEFINE_ENUM(EX_BLOCK_AGE);
+TRACE_DEFINE_ENUM(CP_PHASE_START_BLOCK_OPS);
+TRACE_DEFINE_ENUM(CP_PHASE_FINISH_BLOCK_OPS);
+TRACE_DEFINE_ENUM(CP_PHASE_FINISH_CHECKPOINT);
 
 #define show_block_type(type)						\
 	__print_symbolic(type,						\

@@ -175,6 +178,12 @@ TRACE_DEFINE_ENUM(EX_BLOCK_AGE);
 #define S_ALL_PERM	(S_ISUID | S_ISGID | S_ISVTX |	\
 			S_IRWXU | S_IRWXG | S_IRWXO)
 
+#define show_cp_phase(phase)					\
+	__print_symbolic(phase,						\
+		{ CP_PHASE_START_BLOCK_OPS,		"start block_ops" },			\
+		{ CP_PHASE_FINISH_BLOCK_OPS,	"finish block_ops" },			\
+		{ CP_PHASE_FINISH_CHECKPOINT,	"finish checkpoint" })
+
 struct f2fs_sb_info;
 struct f2fs_io_info;
 struct extent_info;

@@ -1541,26 +1550,26 @@ TRACE_EVENT(f2fs_readpages,
 
 TRACE_EVENT(f2fs_write_checkpoint,
 
-	TP_PROTO(struct super_block *sb, int reason, const char *msg),
+	TP_PROTO(struct super_block *sb, int reason, u16 phase),
 
-	TP_ARGS(sb, reason, msg),
+	TP_ARGS(sb, reason, phase),
 
 	TP_STRUCT__entry(
 		__field(dev_t,	dev)
 		__field(int,	reason)
-		__string(dest_msg, msg)
+		__field(u16, phase)
 	),
 
 	TP_fast_assign(
 		__entry->dev		= sb->s_dev;
 		__entry->reason		= reason;
-		__assign_str(dest_msg);
+		__entry->phase		= phase;
 	),
 
 	TP_printk("dev = (%d,%d), checkpoint for %s, state = %s",
 		show_dev(__entry->dev),
 		show_cpreason(__entry->reason),
-		__get_str(dest_msg))
+		show_cp_phase(__entry->phase))
 );
 
 DECLARE_EVENT_CLASS(f2fs_discard,
Signature · 1 line
2.53.0
maintainer
#4 lore raw

PATCH 4/5 f2fs: detect more inconsistent cases in sanity_check_node_footer()

In reply to Sasha Levin

From: Chao Yu <[email protected]>

[ Upstream commit 93ffb6c28ff180560d2d7313ac106efcd9e012b8 ]

Let's enhance sanity_check_node_footer() to detect more inconsistent cases as below:

Node Type Node Footer Info
=================== =============================
NODE_TYPE_REGULAR inode = true and xnode = true
NODE_TYPE_INODE inode = false or xnode = true
NODE_TYPE_XATTR inode = true or xnode = false
NODE_TYPE_NON_INODE inode = false

Signed-off-by Chao Yu <[email protected]>
Signed-off-by Jaegeuk Kim <[email protected]>

Stable-dep-of: 8712353ed80f ("f2fs: fix to do sanity check on f2fs_get_node_folio_ra()")

Signed-off-by Sasha Levin <[email protected]>
---
 fs/f2fs/node.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)
fs/f2fs/node.c +12 -3
index ca3dad7418b268..bf06c9582ae49b 100644
@@ -1504,20 +1504,29 @@ int f2fs_sanity_check_node_footer(struct f2fs_sb_info *sbi,
 					struct folio *folio, pgoff_t nid,
 					enum node_type ntype, bool in_irq)
 {
+	bool is_inode, is_xnode;
+
 	if (unlikely(nid != nid_of_node(folio)))
 		goto out_err;
 
+	is_inode = IS_INODE(folio);
+	is_xnode = f2fs_has_xattr_block(ofs_of_node(folio));
+
 	switch (ntype) {
+	case NODE_TYPE_REGULAR:
+		if (is_inode && is_xnode)
+			goto out_err;
+		break;
 	case NODE_TYPE_INODE:
-		if (!IS_INODE(folio))
+		if (!is_inode || is_xnode)
 			goto out_err;
 		break;
 	case NODE_TYPE_XATTR:
-		if (!f2fs_has_xattr_block(ofs_of_node(folio)))
+		if (is_inode || !is_xnode)
 			goto out_err;
 		break;
 	case NODE_TYPE_NON_INODE:
-		if (IS_INODE(folio))
+		if (is_inode)
 			goto out_err;
 		break;
 	default:
Signature · 1 line
2.53.0
maintainer
#5 lore raw

PATCH 5/5 f2fs: fix to do sanity check on f2fs_get_node_folio_ra()

In reply to Sasha Levin

From: Chao Yu <[email protected]>

[ Upstream commit 8712353ed80f87271d732297567dcdbe4b84e8c7 ]

kernel BUG at fs/f2fs/file.c:845!

Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5336 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:f2fs_do_truncate_blocks+0x1115/0x1140 fs/f2fs/file.c:845
Code: fc fc 90 0f 0b e8 8b 9d 9a fd 90 0f 0b e8 83 9d 9a fd 48 89 df 48 c7 c6 60 d1 1a 8c e8 54 f1 fc fc 90 0f 0b e8 6c 9d 9a fd 90 <0f> 0b e8 64 9d 9a fd 90 0f 0b 90 e9 93 fd ff ff e8 56 9d 9a fd 90
RSP: 0018:ffffc9000e4474c0 EFLAGS: 00010283
RAX: ffffffff842b1d34 RBX: 0000000000000003 RCX: 0000000000100000
RDX: ffffc9000f03a000 RSI: 0000000000035503 RDI: 0000000000035504
RBP: ffffc9000e447608 R08: ffff8880123b0000 R09: 0000000000000002
R10: 00000000fffffffe R11: 0000000000000002 R12: 0000000000000001
R13: 0000000000000000 R14: 1ffff92001c88ea0 R15: 00000000ffff039c
FS:  00007f7e02ee36c0(0000) GS:ffff88808c887000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff0305c4000 CR3: 0000000012d4c000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 f2fs_truncate_blocks+0x10a/0x300 fs/f2fs/file.c:882
 f2fs_truncate+0x471/0x7c0 fs/f2fs/file.c:940
 f2fs_evict_inode+0xa3f/0x1ac0 fs/f2fs/inode.c:907
 evict+0x61e/0xb10 fs/inode.c:841
 f2fs_fill_super+0x5f43/0x78f0 fs/f2fs/super.c:5224
 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
 vfs_get_tree+0x92/0x2a0 fs/super.c:1754
 fc_mount fs/namespace.c:1193 [inline]
 do_new_mount_fc fs/namespace.c:3758 [inline]
 do_new_mount+0x341/0xd30 fs/namespace.c:3834
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
	count = ADDRS_PER_PAGE(dn.node_folio, inode);

	count -= dn.ofs_in_node;
	f2fs_bug_on(sbi, count < 0);

The fuzz test will trigger above bug_on in f2fs.

The root cause should be: in the corrupted inode, there is a direct node which has the same ino and nid in its footer, so in f2fs_do_truncate_blocks(), after f2fs_get_dnode_of_data() finds such dnode:
1) ADDRS_PER_PAGE(dn.node_folio, inode) will return 923
2) once dn.ofs_in_node points to addr[923, 1017]
Then it will trigger the system panic.

Let's introduce NODE_TYPE_NON_IXNODE to indicate current node should not be an inode or xattr node, and then use it in below path to detect inconsistent node chain in inode mapping table:

- f2fs_do_truncate_blocks
- f2fs_get_dnode_of_data
- f2fs_get_node_folio_ra
- __get_node_folio
- f2fs_sanity_check_node_footer
- case NODE_TYPE_NON_IXNODE -> check whether it is inode|xnode

Cc [email protected]
Reported-by [email protected]
Closes https://lore.kernel.org/all/[email protected] open here
Signed-off-by Chao Yu <[email protected]>
Signed-off-by Jaegeuk Kim <[email protected]>
Signed-off-by Sasha Levin <[email protected]>
---
 fs/f2fs/f2fs.h | 1 +
 fs/f2fs/node.c | 6 +++++-
 2 files changed, 6 insertions(+), 1 deletion(-)
fs/f2fs/f2fs.h +1 -0
index 31252fb1b06bd1..4cdef8c27ce059 100644
@@ -1533,6 +1533,7 @@ enum node_type {
 	NODE_TYPE_INODE,
 	NODE_TYPE_XATTR,
 	NODE_TYPE_NON_INODE,
+	NODE_TYPE_NON_IXNODE,	/* non inode and xnode */
 };
fs/f2fs/node.c +5 -1
index bf06c9582ae49b..16388c2941bab5 100644
@@ -1529,6 +1529,10 @@ int f2fs_sanity_check_node_footer(struct f2fs_sb_info *sbi,
 		if (is_inode)
 			goto out_err;
 		break;
+	case NODE_TYPE_NON_IXNODE:
+		if (is_inode || is_xnode)
+			goto out_err;
+		break;
 	default:
 		break;
 	}

@@ -1622,7 +1626,7 @@ static struct folio *f2fs_get_node_folio_ra(struct folio *parent, int start)
 	struct f2fs_sb_info *sbi = F2FS_F_SB(parent);
 	nid_t nid = get_nid(parent, start, false);
 
-	return __get_node_folio(sbi, nid, parent, start, NODE_TYPE_REGULAR);
+	return __get_node_folio(sbi, nid, parent, start, NODE_TYPE_NON_IXNODE);
 }
 
 static void flush_inline_data(struct f2fs_sb_info *sbi, nid_t ino)
Signature · 1 line
2.53.0