linux-stable.git/fs, branch v6.1.187 Linux kernel stable tree fuse: fix invalidate lock leak on open O_TRUNC DAX failure 2026-09-02T12:28:35+00:00 Baokun Li libaokun@linux.alibaba.com 2026-08-17T15:18:01+00:00 a61524da59a2f5ac9c8de23ff98b30da769ab144 commit a927f1867e61b78f39f9da0bbba3c98c2ca151fe upstream. fuse_open() takes filemap_invalidate_lock() for a DAX truncate (dax_truncate = true) and releases it before the out_inode_unlock label. But when fuse_dax_break_layouts() fails, the goto out_inode_unlock skips the unlock and leaks the rwsem, so any later fault or truncate on the file stalls on the stale lock. fuse_dax_break_layouts() can fail with -ERESTARTSYS when a signal interrupts the wait for busy DAX pages to drain: open("file", O_RDWR | O_TRUNC) └─ fuse_open() ├─ filemap_invalidate_lock() # dax_truncate └─ fuse_dax_break_layouts() └─ dax_break_layout() └─ wait_page_idle() # TASK_INTERRUPTIBLE └─ fuse_wait_dax_page() # unlock, schedule, re-lock └─ signal → -ERESTARTSYS goto out_inode_unlock # <- lock leaked Fix this by moving filemap_invalidate_unlock() below the label so that all error paths release the lock, and rename the label to out_unlock as it now covers more than just the inode lock. Fixes: 2fdbb8dd0155 ("fuse: fix deadlock between atomic O_TRUNC and page invalidation") Cc: stable@vger.kernel.org # v6.0+ Signed-off-by: Baokun Li <libaokun@linux.alibaba.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a927f1867e61b78f39f9da0bbba3c98c2ca151fe upstream.

fuse_open() takes filemap_invalidate_lock() for a DAX truncate
(dax_truncate = true) and releases it before the out_inode_unlock
label.  But when fuse_dax_break_layouts() fails, the goto
out_inode_unlock skips the unlock and leaks the rwsem, so any later
fault or truncate on the file stalls on the stale lock.

fuse_dax_break_layouts() can fail with -ERESTARTSYS when a signal
interrupts the wait for busy DAX pages to drain:

  open("file", O_RDWR | O_TRUNC)
  └─ fuse_open()
     ├─ filemap_invalidate_lock()        # dax_truncate
     └─ fuse_dax_break_layouts()
        └─ dax_break_layout()
           └─ wait_page_idle()           # TASK_INTERRUPTIBLE
              └─ fuse_wait_dax_page()    # unlock, schedule, re-lock
                 └─ signal → -ERESTARTSYS
     goto out_inode_unlock               # <- lock leaked

Fix this by moving filemap_invalidate_unlock() below the label so
that all error paths release the lock, and rename the label to
out_unlock as it now covers more than just the inode lock.

Fixes: 2fdbb8dd0155 ("fuse: fix deadlock between atomic O_TRUNC and page invalidation")
Cc: stable@vger.kernel.org # v6.0+
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
fuse: fix invalidate lock leak on setattr writeback failure 2026-09-02T12:28:35+00:00 Baokun Li libaokun@linux.alibaba.com 2026-08-17T15:18:00+00:00 03cfeeb135428fa83f0791d3f8f94d9298cae695 commit 9afeca0d569c9fc89d758fe7a9339d1e8afb1546 upstream. fuse_do_setattr() takes filemap_invalidate_lock() for a DAX truncate (fault_blocked = true) and releases it at the out:/error: labels. But when a writeback flush is also needed, a write_inode_now() failure returns directly and leaks the lock, so any later fault or truncate on the file stalls on the stale rwsem. For example, truncate(2) on a setuid file reaches fuse_do_setattr() with both ATTR_SIZE and ATTR_MODE set: truncate(2) └─ do_truncate() ├─ dentry_needs_remove_privs() # S_ISUID └─ notify_change() # KILL_SUID -> ATTR_MODE └─ fuse_setattr() # no killpriv: │ # ia_valid |= ATTR_MODE └─ fuse_do_setattr() ├─ filemap_invalidate_lock() # IS_DAX && is_truncate └─ write_inode_now() # is_wb && ATTR_MODE └─ if (err) # e.g. daemon -> -EIO return err # <- lock leaked Fix this by adding an unlock label that releases the lock before returning the error, and use it for the fuse_dax_break_layouts() failure path as well. Fixes: 6ae330cad6ef ("virtiofs: serialize truncate/punch_hole and dax fault path") Cc: stable@vger.kernel.org # v5.10+ Signed-off-by: Baokun Li <libaokun@linux.alibaba.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9afeca0d569c9fc89d758fe7a9339d1e8afb1546 upstream.

fuse_do_setattr() takes filemap_invalidate_lock() for a DAX truncate
(fault_blocked = true) and releases it at the out:/error: labels.  But
when a writeback flush is also needed, a write_inode_now() failure
returns directly and leaks the lock, so any later fault or truncate on
the file stalls on the stale rwsem.

For example, truncate(2) on a setuid file reaches fuse_do_setattr()
with both ATTR_SIZE and ATTR_MODE set:

  truncate(2)
  └─ do_truncate()
     ├─ dentry_needs_remove_privs()         # S_ISUID
     └─ notify_change()                     # KILL_SUID -> ATTR_MODE
        └─ fuse_setattr()                   # no killpriv:
           │                                #   ia_valid |= ATTR_MODE
           └─ fuse_do_setattr()
              ├─ filemap_invalidate_lock()  # IS_DAX && is_truncate
              └─ write_inode_now()          # is_wb && ATTR_MODE
                 └─ if (err)                # e.g. daemon -> -EIO
                    return err              # <- lock leaked

Fix this by adding an unlock label that releases the lock before
returning the error, and use it for the fuse_dax_break_layouts()
failure path as well.

Fixes: 6ae330cad6ef ("virtiofs: serialize truncate/punch_hole and dax fault path")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nilfs2: reject invalid block index in GC ioctl 2026-09-02T12:28:33+00:00 Ryusuke Konishi konishi.ryusuke@gmail.com 2026-08-26T01:17:50+00:00 3bd064ccc70b85f9a3d53aece29dc8473be5a226 [ Upstream commit a1735eae55448bc79c2da6593455791e886f6ed8 ] Syzbot reported list corruption caused by a double list_add_tail() call on bh->b_assoc_buffers within nilfs_lookup_dirty_data_buffers(). Analysis revealed that the root cause was the insertion of a page/folio with a page index of ULONG_MAX into the page cache via the GC ioctl. filemap_get_folios_tag(), called by nilfs_lookup_dirty_data_buffers(), repeatedly detects a dirty folio with a page index of ULONG_MAX due to index wrap-around, leading to duplicate processing of dirty buffers. As a preparatory step, the GC ioctl loads the page/folio of the block to be moved during GC and inserts it into the page cache based on information in the nilfs_vdesc structure passed as an argument. Normally, this does not cause issues because the user-space GC library configures the nilfs_vdesc structure properly. However, since there is no range check on the parameters determining the page index, a request with artificially crafted parameters -- such as those generated by Syzbot -- can result in a page/folio being inserted with a page index of ULONG_MAX, triggering the above problem. This resolves the issue by checking the ranges of 'vd_offset' and 'vd_vblocknr' in the nilfs_vdesc structure that determine the page index, thereby preventing the invalid page/folio insertions. Reported-by: syzbot+c37bed40868932d790e9@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=c37bed40868932d790e9 Fixes: 7942b919f732 ("nilfs2: ioctl operations") Cc: wuyankun <wuyankun@uniontech.com> Cc: stable@vger.kernel.org Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit a1735eae55448bc79c2da6593455791e886f6ed8 ]

Syzbot reported list corruption caused by a double list_add_tail() call on
bh->b_assoc_buffers within nilfs_lookup_dirty_data_buffers().

Analysis revealed that the root cause was the insertion of a page/folio
with a page index of ULONG_MAX into the page cache via the GC ioctl.
filemap_get_folios_tag(), called by nilfs_lookup_dirty_data_buffers(),
repeatedly detects a dirty folio with a page index of ULONG_MAX due to
index wrap-around, leading to duplicate processing of dirty buffers.

As a preparatory step, the GC ioctl loads the page/folio of the block to
be moved during GC and inserts it into the page cache based on information
in the nilfs_vdesc structure passed as an argument.  Normally, this does
not cause issues because the user-space GC library configures the
nilfs_vdesc structure properly.  However, since there is no range check on
the parameters determining the page index, a request with artificially
crafted parameters -- such as those generated by Syzbot -- can result in a
page/folio being inserted with a page index of ULONG_MAX, triggering the
above problem.

This resolves the issue by checking the ranges of 'vd_offset' and
'vd_vblocknr' in the nilfs_vdesc structure that determine the page index,
thereby preventing the invalid page/folio insertions.

Reported-by: syzbot+c37bed40868932d790e9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c37bed40868932d790e9
Fixes: 7942b919f732 ("nilfs2: ioctl operations")
Cc: wuyankun <wuyankun@uniontech.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nilfs2: correct return value kernel-doc descriptions for ioctl functions 2026-09-02T12:28:33+00:00 Ryusuke Konishi konishi.ryusuke@gmail.com 2026-08-26T01:17:49+00:00 0f2606a7c88cc36ccfe73390a34bdabb2d888752 [ Upstream commit 17c46a45cdb94c500f4e93b176cdd61931b03020 ] Patch series "nilfs2: fix kernel-doc comments for function return values", v2. This series fixes the inadequacies in the return value descriptions in nilfs2's kernel-doc comments (mainly incorrect formatting), as well as the lack of return value descriptions themselves, and fixes most of the remaining warnings that are output when the kernel-doc script is run with the "-Wall" option. This patch (of 7): In the kernel-doc comments for functions, there are many cases where the format of the return value description is inaccurate, such as "Return Value: ...", which causes many warnings to be output when the kernel-doc script is executed with the "-Wall" option. This fixes such incorrectly formatted return value descriptions for ioctl functions. Link: https://lkml.kernel.org/r/20250110010530.21872-1-konishi.ryusuke@gmail.com Link: https://lkml.kernel.org/r/20250110010530.21872-2-konishi.ryusuke@gmail.com Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> Cc: "Brian G ." <gissf1@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Stable-dep-of: a1735eae5544 ("nilfs2: reject invalid block index in GC ioctl") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 17c46a45cdb94c500f4e93b176cdd61931b03020 ]

Patch series "nilfs2: fix kernel-doc comments for function return values",
v2.

This series fixes the inadequacies in the return value descriptions in
nilfs2's kernel-doc comments (mainly incorrect formatting), as well as the
lack of return value descriptions themselves, and fixes most of the
remaining warnings that are output when the kernel-doc script is run with
the "-Wall" option.

This patch (of 7):

In the kernel-doc comments for functions, there are many cases where the
format of the return value description is inaccurate, such as "Return
Value: ...", which causes many warnings to be output when the kernel-doc
script is executed with the "-Wall" option.

This fixes such incorrectly formatted return value descriptions for ioctl
functions.

Link: https://lkml.kernel.org/r/20250110010530.21872-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20250110010530.21872-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: "Brian G ." <gissf1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: a1735eae5544 ("nilfs2: reject invalid block index in GC ioctl")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ext4: propagate errors from fast commit range replay 2026-09-02T12:28:33+00:00 Guanghui Yang 3497809730@qq.com 2026-08-26T00:49:49+00:00 ab6a9909181189cfba386c4a2144b0e578725949 [ Upstream commit d8b8dd3530bf41e14b118702cdaf9de64bb96885 ] ext4_fc_replay() stops replaying fast commit tags only when a tag handler returns a negative error. However, ext4_fc_replay_add_range() and ext4_fc_replay_del_range() currently return 0 from their common exit paths even after internal failures. This hides errors from ext4_fc_record_modified_inode(), ext4_map_blocks(), ext4_find_extent(), ext4_ext_insert_extent(), ext4_ext_replay_update_ex(), and ext4_ext_remove_space(). As a result, a failed ADD_RANGE or DEL_RANGE replay can be treated as successful and the replay code may continue with subsequent fast commit tags. This is particularly problematic for DEL_RANGE because it may already have marked blocks as free before ext4_ext_remove_space() fails. If the error is swallowed, replay may continue from a partially applied range operation. Return the saved error from the common exit paths and make the ERR_PTR() cases in ADD_RANGE store PTR_ERR() before jumping to out. Fixes: 8016e29f4362 ("ext4: fast commit recovery path") Cc: stable@vger.kernel.org Signed-off-by: Guanghui Yang <3497809730@qq.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://patch.msgid.link/tencent_E3622146846A84C75C31C7D32AC4D5AD0605@qq.com Signed-off-by: Theodore Ts'o <tytso@mit.edu> [ kept the existing `ext4_find_extent(inode, cur, NULL, 0)` call and dropped the `ext4_ext_insert_extent()` error-capture hunk, since this tree's extents API predates the ppath rework and already returns errors via `int` ] Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit d8b8dd3530bf41e14b118702cdaf9de64bb96885 ]

ext4_fc_replay() stops replaying fast commit tags only when a tag
handler returns a negative error. However, ext4_fc_replay_add_range()
and ext4_fc_replay_del_range() currently return 0 from their common
exit paths even after internal failures.

This hides errors from ext4_fc_record_modified_inode(),
ext4_map_blocks(), ext4_find_extent(), ext4_ext_insert_extent(),
ext4_ext_replay_update_ex(), and ext4_ext_remove_space(). As a result,
a failed ADD_RANGE or DEL_RANGE replay can be treated as successful and
the replay code may continue with subsequent fast commit tags.

This is particularly problematic for DEL_RANGE because it may already
have marked blocks as free before ext4_ext_remove_space() fails. If the
error is swallowed, replay may continue from a partially applied range
operation.

Return the saved error from the common exit paths and make the
ERR_PTR() cases in ADD_RANGE store PTR_ERR() before jumping to out.

Fixes: 8016e29f4362 ("ext4: fast commit recovery path")
Cc: stable@vger.kernel.org
Signed-off-by: Guanghui Yang <3497809730@qq.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/tencent_E3622146846A84C75C31C7D32AC4D5AD0605@qq.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
[ kept the existing `ext4_find_extent(inode, cur, NULL, 0)` call and dropped the `ext4_ext_insert_extent()` error-capture hunk, since this tree's extents API predates the ppath rework and already returns errors via `int` ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "smb: client: use kvzalloc() for megabyte buffer in simple fallocate" 2026-09-02T12:28:33+00:00 Sasha Levin sashal@kernel.org 2026-08-30T15:08:13+00:00 2a9717e2e9f0b50bcd6b0abaa4668a8c6f6f4f7c This reverts commit 1233c883cceb2e859b14abef4087f400e92490c7. Signed-off-by: Sasha Levin <sashal@kernel.org> 
This reverts commit 1233c883cceb2e859b14abef4087f400e92490c7.

Signed-off-by: Sasha Levin <sashal@kernel.org>
exfat: fix double free in delayed_free 2026-09-02T12:28:32+00:00 Namjae Jeon linkinjeon@kernel.org 2025-04-01T04:50:39+00:00 ea27703eb0efbadcd45b9949526160ed90536a72 [ Upstream commit 1f3d9724e16d62c7d42c67d6613b8512f2887c22 ] The double free could happen in the following path. exfat_create_upcase_table() exfat_create_upcase_table() : return error exfat_free_upcase_table() : free ->vol_utbl exfat_load_default_upcase_table : return error exfat_kill_sb() delayed_free() exfat_free_upcase_table() <--------- double free This patch set ->vol_util as NULL after freeing it. Reported-by: Jianzhou Zhao <xnxc22xnxc22@qq.com> Signed-off-by: Namjae Jeon <linkinjeon@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 1f3d9724e16d62c7d42c67d6613b8512f2887c22 ]

The double free could happen in the following path.

exfat_create_upcase_table()
        exfat_create_upcase_table() : return error
        exfat_free_upcase_table() : free ->vol_utbl
        exfat_load_default_upcase_table : return error
     exfat_kill_sb()
           delayed_free()
                  exfat_free_upcase_table() <--------- double free
This patch set ->vol_util as NULL after freeing it.

Reported-by: Jianzhou Zhao <xnxc22xnxc22@qq.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jfs: Fix null-ptr-deref in jfs_ioc_trim 2026-09-02T12:28:31+00:00 Dylan Wolff wolffd@comp.nus.edu.sg 2025-03-12T08:02:00+00:00 4a2de0f5b8d7f218bea5bd43d30b466e8b272b8d [ Upstream commit a4685408ff6c3e2af366ad9a7274f45ff3f394ee ] [ Syzkaller Report ] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000087: 0000 [#1 KASAN: null-ptr-deref in range [0x0000000000000438-0x000000000000043f] CPU: 2 UID: 0 PID: 10614 Comm: syz-executor.0 Not tainted 6.13.0-rc6-gfbfd64d25c7a-dirty #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Sched_ext: serialise (enabled+all), task: runnable_at=-30ms RIP: 0010:jfs_ioc_trim+0x34b/0x8f0 Code: e7 e8 59 a4 87 fe 4d 8b 24 24 4d 8d bc 24 38 04 00 00 48 8d 93 90 82 fe ff 4c 89 ff 31 f6 RSP: 0018:ffffc900055f7cd0 EFLAGS: 00010206 RAX: 0000000000000087 RBX: 00005866a9e67ff8 RCX: 000000000000000a RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001 RBP: dffffc0000000000 R08: ffff88807c180003 R09: 1ffff1100f830000 R10: dffffc0000000000 R11: ffffed100f830001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000438 FS: 00007fe520225640(0000) GS:ffff8880b7e80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005593c91b2c88 CR3: 000000014927c000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? __die_body+0x61/0xb0 ? die_addr+0xb1/0xe0 ? exc_general_protection+0x333/0x510 ? asm_exc_general_protection+0x26/0x30 ? jfs_ioc_trim+0x34b/0x8f0 jfs_ioctl+0x3c8/0x4f0 ? __pfx_jfs_ioctl+0x10/0x10 ? __pfx_jfs_ioctl+0x10/0x10 __se_sys_ioctl+0x269/0x350 ? __pfx___se_sys_ioctl+0x10/0x10 ? do_syscall_64+0xfb/0x210 do_syscall_64+0xee/0x210 ? syscall_exit_to_user_mode+0x1e0/0x330 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe51f4903ad Code: c3 e8 a7 2b 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d RSP: 002b:00007fe5202250c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fe51f5cbf80 RCX: 00007fe51f4903ad RDX: 0000000020000680 RSI: 00000000c0185879 RDI: 0000000000000005 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe520225640 R13: 000000000000000e R14: 00007fe51f44fca0 R15: 00007fe52021d000 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:jfs_ioc_trim+0x34b/0x8f0 Code: e7 e8 59 a4 87 fe 4d 8b 24 24 4d 8d bc 24 38 04 00 00 48 8d 93 90 82 fe ff 4c 89 ff 31 f6 RSP: 0018:ffffc900055f7cd0 EFLAGS: 00010206 RAX: 0000000000000087 RBX: 00005866a9e67ff8 RCX: 000000000000000a RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001 RBP: dffffc0000000000 R08: ffff88807c180003 R09: 1ffff1100f830000 R10: dffffc0000000000 R11: ffffed100f830001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000438 FS: 00007fe520225640(0000) GS:ffff8880b7e80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005593c91b2c88 CR3: 000000014927c000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Kernel panic - not syncing: Fatal exception [ Analysis ] We believe that we have found a concurrency bug in the `fs/jfs` module that results in a null pointer dereference. There is a closely related issue which has been fixed: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d6c1b3599b2feb5c7291f5ac3a36e5fa7cedb234 ... but, unfortunately, the accepted patch appears to still be susceptible to a null pointer dereference under some interleavings. To trigger the bug, we think that `JFS_SBI(ipbmap->i_sb)->bmap` is set to NULL in `dbFreeBits` and then dereferenced in `jfs_ioc_trim`. This bug manifests quite rarely under normal circumstances, but is triggereable from a syz-program. Reported-and-tested-by: Dylan J. Wolff<wolffd@comp.nus.edu.sg> Reported-and-tested-by: Jiacheng Xu <stitch@zju.edu.cn> Signed-off-by: Dylan J. Wolff<wolffd@comp.nus.edu.sg> Signed-off-by: Jiacheng Xu <stitch@zju.edu.cn> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit a4685408ff6c3e2af366ad9a7274f45ff3f394ee ]

[ Syzkaller Report ]

Oops: general protection fault, probably for non-canonical address
0xdffffc0000000087: 0000 [#1
KASAN: null-ptr-deref in range [0x0000000000000438-0x000000000000043f]
CPU: 2 UID: 0 PID: 10614 Comm: syz-executor.0 Not tainted
6.13.0-rc6-gfbfd64d25c7a-dirty #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Sched_ext: serialise (enabled+all), task: runnable_at=-30ms
RIP: 0010:jfs_ioc_trim+0x34b/0x8f0
Code: e7 e8 59 a4 87 fe 4d 8b 24 24 4d 8d bc 24 38 04 00 00 48 8d 93
90 82 fe ff 4c 89 ff 31 f6
RSP: 0018:ffffc900055f7cd0 EFLAGS: 00010206
RAX: 0000000000000087 RBX: 00005866a9e67ff8 RCX: 000000000000000a
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffff88807c180003 R09: 1ffff1100f830000
R10: dffffc0000000000 R11: ffffed100f830001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000438
FS:  00007fe520225640(0000) GS:ffff8880b7e80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005593c91b2c88 CR3: 000000014927c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
? __die_body+0x61/0xb0
? die_addr+0xb1/0xe0
? exc_general_protection+0x333/0x510
? asm_exc_general_protection+0x26/0x30
? jfs_ioc_trim+0x34b/0x8f0
jfs_ioctl+0x3c8/0x4f0
? __pfx_jfs_ioctl+0x10/0x10
? __pfx_jfs_ioctl+0x10/0x10
__se_sys_ioctl+0x269/0x350
? __pfx___se_sys_ioctl+0x10/0x10
? do_syscall_64+0xfb/0x210
do_syscall_64+0xee/0x210
? syscall_exit_to_user_mode+0x1e0/0x330
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe51f4903ad
Code: c3 e8 a7 2b 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 89 f8 48
89 f7 48 89 d6 48 89 ca 4d
RSP: 002b:00007fe5202250c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe51f5cbf80 RCX: 00007fe51f4903ad
RDX: 0000000020000680 RSI: 00000000c0185879 RDI: 0000000000000005
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe520225640
R13: 000000000000000e R14: 00007fe51f44fca0 R15: 00007fe52021d000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:jfs_ioc_trim+0x34b/0x8f0
Code: e7 e8 59 a4 87 fe 4d 8b 24 24 4d 8d bc 24 38 04 00 00 48 8d 93
90 82 fe ff 4c 89 ff 31 f6
RSP: 0018:ffffc900055f7cd0 EFLAGS: 00010206
RAX: 0000000000000087 RBX: 00005866a9e67ff8 RCX: 000000000000000a
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: dffffc0000000000 R08: ffff88807c180003 R09: 1ffff1100f830000
R10: dffffc0000000000 R11: ffffed100f830001 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000438
FS:  00007fe520225640(0000) GS:ffff8880b7e80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005593c91b2c88 CR3: 000000014927c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Kernel panic - not syncing: Fatal exception

[ Analysis ]

We believe that we have found a concurrency bug in the `fs/jfs` module
that results in a null pointer dereference. There is a closely related
issue which has been fixed:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d6c1b3599b2feb5c7291f5ac3a36e5fa7cedb234

... but, unfortunately, the accepted patch appears to still be
susceptible to a null pointer dereference under some interleavings.

To trigger the bug, we think that `JFS_SBI(ipbmap->i_sb)->bmap` is set
to NULL in `dbFreeBits` and then dereferenced in `jfs_ioc_trim`. This
bug manifests quite rarely under normal circumstances, but is
triggereable from a syz-program.

Reported-and-tested-by: Dylan J. Wolff<wolffd@comp.nus.edu.sg>
Reported-and-tested-by: Jiacheng Xu <stitch@zju.edu.cn>
Signed-off-by: Dylan J. Wolff<wolffd@comp.nus.edu.sg>
Signed-off-by: Jiacheng Xu <stitch@zju.edu.cn>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jfs: add check read-only before txBeginAnon() call 2026-09-02T12:28:31+00:00 Vasiliy Kovalev kovalev@altlinux.org 2024-12-24T14:49:13+00:00 469bd67fc338e77d7585e4f20d4212afd44fefdc [ Upstream commit 0176e69743ecc02961f2ae1ea42439cd2bf9ed58 ] Added a read-only check before calling `txBeginAnon` in `extAlloc` and `extRecord`. This prevents modification attempts on a read-only mounted filesystem, avoiding potential errors or crashes. Call trace: txBeginAnon+0xac/0x154 extAlloc+0xe8/0xdec fs/jfs/jfs_extent.c:78 jfs_get_block+0x340/0xb98 fs/jfs/inode.c:248 __block_write_begin_int+0x580/0x166c fs/buffer.c:2128 __block_write_begin fs/buffer.c:2177 [inline] block_write_begin+0x98/0x11c fs/buffer.c:2236 jfs_write_begin+0x44/0x88 fs/jfs/inode.c:299 Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+4e89b5368baba8324e07@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=4e89b5368baba8324e07 Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 0176e69743ecc02961f2ae1ea42439cd2bf9ed58 ]

Added a read-only check before calling `txBeginAnon` in `extAlloc`
and `extRecord`. This prevents modification attempts on a read-only
mounted filesystem, avoiding potential errors or crashes.

Call trace:
 txBeginAnon+0xac/0x154
 extAlloc+0xe8/0xdec fs/jfs/jfs_extent.c:78
 jfs_get_block+0x340/0xb98 fs/jfs/inode.c:248
 __block_write_begin_int+0x580/0x166c fs/buffer.c:2128
 __block_write_begin fs/buffer.c:2177 [inline]
 block_write_begin+0x98/0x11c fs/buffer.c:2236
 jfs_write_begin+0x44/0x88 fs/jfs/inode.c:299

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot+4e89b5368baba8324e07@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=4e89b5368baba8324e07
Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
jfs: add check read-only before truncation in jfs_truncate_nolock() 2026-09-02T12:28:31+00:00 Vasiliy Kovalev kovalev@altlinux.org 2024-12-24T14:49:14+00:00 b57a8983916fc2cf54fd8de3afc733c6b3d1c0e5 [ Upstream commit b5799dd77054c1ec49b0088b006c9908e256843b ] Added a check for "read-only" mode in the `jfs_truncate_nolock` function to avoid errors related to writing to a read-only filesystem. Call stack: block_write_begin() { jfs_write_failed() { jfs_truncate() { jfs_truncate_nolock() { txEnd() { ... log = JFS_SBI(tblk->sb)->log; // (log == NULL) If the `isReadOnly(ip)` condition is triggered in `jfs_truncate_nolock`, the function execution will stop, and no further data modification will occur. Instead, the `xtTruncate` function will be called with the "COMMIT_WMAP" flag, preventing modifications in "read-only" mode. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+4e89b5368baba8324e07@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=4e89b5368baba8324e07 Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit b5799dd77054c1ec49b0088b006c9908e256843b ]

Added a check for "read-only" mode in the `jfs_truncate_nolock`
function to avoid errors related to writing to a read-only
filesystem.

Call stack:

block_write_begin() {
  jfs_write_failed() {
    jfs_truncate() {
      jfs_truncate_nolock() {
        txEnd() {
          ...
          log = JFS_SBI(tblk->sb)->log;
          // (log == NULL)

If the `isReadOnly(ip)` condition is triggered in
`jfs_truncate_nolock`, the function execution will stop, and no
further data modification will occur. Instead, the `xtTruncate`
function will be called with the "COMMIT_WMAP" flag, preventing
modifications in "read-only" mode.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot+4e89b5368baba8324e07@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=4e89b5368baba8324e07
Signed-off-by: Vasiliy Kovalev <kovalev@altlinux.org>
Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>