* general protection fault in mount_fs
@ 2018-04-05 2:02 syzbot
2018-05-15 10:08 ` [PATCH] hfsplus: don't return 0 when fill_super() failed Tetsuo Handa
0 siblings, 1 reply; 5+ messages in thread
From: syzbot @ 2018-04-05 2:02 UTC (permalink / raw)
To: linux-fsdevel, linux-kernel, syzkaller-bugs, viro
Hello,
syzbot hit the following crash on upstream commit
3e968c9f1401088abc9a19ae6ff571644d37a355 (Wed Apr 4 21:19:24 2018 +0000)
Merge tag 'ext4_for_linus' of
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
syzbot dashboard link:
https://syzkaller.appspot.com/bug?extid=01ffaf5d9568dd1609f7
C reproducer: https://syzkaller.appspot.com/x/repro.c?id=6269272955289600
syzkaller reproducer:
https://syzkaller.appspot.com/x/repro.syz?id=5190169938362368
Raw console output:
https://syzkaller.appspot.com/x/log.txt?id=5077254979715072
Kernel config:
https://syzkaller.appspot.com/x/.config?id=9118669095563550941
compiler: gcc (GCC) 7.1.1 20170620
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+01ffaf5d9568dd1609f7@syzkaller.appspotmail.com
It will help syzbot understand when the bug is fixed. See footer for
details.
If you forward the report, please keep this part and the footer.
hfsplus: failed to load root directory
hfsplus: failed to load root directory
hfsplus: failed to load root directory
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 5704 Comm: syzkaller335224 Not tainted 4.16.0+ #15
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:mount_fs+0x92/0x2d0 fs/super.c:1227
RSP: 0018:ffff8801acc9fad0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff81b2ddaa
RDX: 0000000000000019 RSI: 0000000000000000 RDI: 00000000000000c8
RBP: ffff8801acc9fb00 R08: 1ffff10035993e87 R09: ffffed0035993efc
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff886b29c0
R13: ffff8801c6243000 R14: ffff8801ac942ac0 R15: 0000000000000000
FS: 00007f8ca5272700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000004c5198 CR3: 00000001af14e000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
vfs_kern_mount.part.26+0xc6/0x4a0 fs/namespace.c:1037
vfs_kern_mount fs/namespace.c:2514 [inline]
do_new_mount fs/namespace.c:2517 [inline]
do_mount+0xea4/0x2b90 fs/namespace.c:2847
ksys_mount+0xab/0x120 fs/namespace.c:3063
SYSC_mount fs/namespace.c:3077 [inline]
SyS_mount+0x39/0x50 fs/namespace.c:3074
do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x44a34a
RSP: 002b:00007f8ca5271d38 EFLAGS: 00000297 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000318 RCX: 000000000044a34a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f8ca5271d50
RBP: 00000000006e39c4 R08: 0000000020000140 R09: 000000000000000a
R10: 0000000000000000 R11: 0000000000000297 R12: 0000000000000003
R13: 0000000000000004 R14: 00000000006e39c0 R15: 0073756c70736668
Code: 3d 00 f0 ff ff 48 89 c3 0f 87 eb 01 00 00 e8 66 c6 be ff 48 8d bb c8
00 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00
0f 85 08 02 00 00 4c 8b b3 c8 00 00 00 4d 85 f6 0f
RIP: mount_fs+0x92/0x2d0 fs/super.c:1227 RSP: ffff8801acc9fad0
---[ end trace 81f30bb7bca06fe8 ]---
Kernel panic - not syncing: Fatal exception
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: disabled
Rebooting in 86400 seconds..
---
This bug is generated by a dumb bot. It may contain errors.
See https://goo.gl/tpsmEJ for details.
Direct all questions to syzkaller@googlegroups.com.
syzbot will keep track of this bug report.
If you forgot to add the Reported-by tag, once the fix for this bug is
merged
into any tree, please reply to this email with:
#syz fix: exact-commit-title
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^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH] hfsplus: don't return 0 when fill_super() failed 2018-04-05 2:02 general protection fault in mount_fs syzbot @ 2018-05-15 10:08 ` Tetsuo Handa [not found] ` <20180515164221.57cbosgvu6ahslon@eaf> 2018-06-21 1:45 ` Ernesto A. Fernández 0 siblings, 2 replies; 5+ messages in thread From: Tetsuo Handa @ 2018-05-15 10:08 UTC (permalink / raw) To: syzbot, syzkaller-bugs, viro; +Cc: linux-fsdevel, linux-kernel >From f78a5fe168290cb9e009f4d907d04b5bfe277831 Mon Sep 17 00:00:00 2001 From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Date: Tue, 15 May 2018 11:38:38 +0900 Subject: [PATCH] hfsplus: don't return 0 when fill_super() failed syzbot is reporting NULL pointer dereference at mount_fs() [1]. This is because hfsplus_fill_super() is by error returning 0 when hfsplus_fill_super() detected invalid filesystem image, and mount_bdev() is returning NULL because dget(s->s_root) == NULL if s->s_root == NULL, and mount_fs() is accessing root->d_sb because IS_ERR(root) == false if root == NULL. Fix this by returning -EINVAL when hfsplus_fill_super() detected invalid filesystem image. [1] https://syzkaller.appspot.com/bug?id=21acb6850cecbc960c927229e597158cf35f33d0 Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: syzbot <syzbot+01ffaf5d9568dd1609f7@syzkaller.appspotmail.com> Cc: Al Viro <viro@zeniv.linux.org.uk> --- fs/hfsplus/super.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c index 513c357..9e690ae 100644 --- a/fs/hfsplus/super.c +++ b/fs/hfsplus/super.c @@ -524,8 +524,10 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) goto out_put_root; if (!hfs_brec_read(&fd, &entry, sizeof(entry))) { hfs_find_exit(&fd); - if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) + if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) { + err = -EINVAL; goto out_put_root; + } inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id)); if (IS_ERR(inode)) { err = PTR_ERR(inode); -- 1.8.3.1 ^ permalink raw reply related [flat|nested] 5+ messages in thread
[parent not found: <20180515164221.57cbosgvu6ahslon@eaf>]
[parent not found: <201805192255.CAD48427.HLtFMOFVOSOQJF@I-love.SAKURA.ne.jp>]
* Re: [PATCH] hfsplus: don't return 0 when fill_super() failed [not found] ` <201805192255.CAD48427.HLtFMOFVOSOQJF@I-love.SAKURA.ne.jp> @ 2018-05-19 23:25 ` Ernesto A. Fernández 2018-05-19 23:47 ` Al Viro 0 siblings, 1 reply; 5+ messages in thread From: Ernesto A. Fernández @ 2018-05-19 23:25 UTC (permalink / raw) To: Tetsuo Handa Cc: ernesto.mnd.fernandez, akpm, viro, syzkaller-bugs, syzbot+01ffaf5d9568dd1609f7, linux-fsdevel On Sat, May 19, 2018 at 10:55:04PM +0900, Tetsuo Handa wrote: > Ernesto A. Fernandez wrote: > > On Tue, May 15, 2018 at 07:08:24PM +0900, Tetsuo Handa wrote: > > > From f78a5fe168290cb9e009f4d907d04b5bfe277831 Mon Sep 17 00:00:00 2001 > > > From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> > > > Date: Tue, 15 May 2018 11:38:38 +0900 > > > Subject: [PATCH] hfsplus: don't return 0 when fill_super() failed > > > > > > syzbot is reporting NULL pointer dereference at mount_fs() [1]. > > > This is because hfsplus_fill_super() is by error returning 0 when > > > hfsplus_fill_super() detected invalid filesystem image, and mount_bdev() > > > is returning NULL because dget(s->s_root) == NULL if s->s_root == NULL, > > > and mount_fs() is accessing root->d_sb because IS_ERR(root) == false > > > if root == NULL. Fix this by returning -EINVAL when hfsplus_fill_super() > > > detected invalid filesystem image. > > > > > > [1] https://syzkaller.appspot.com/bug?id=21acb6850cecbc960c927229e597158cf35f33d0 > > > > > > Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> > > > Reported-by: syzbot <syzbot+01ffaf5d9568dd1609f7@syzkaller.appspotmail.com> > > > Cc: Al Viro <viro@zeniv.linux.org.uk> > > > --- > > > fs/hfsplus/super.c | 4 +++- > > > 1 file changed, 3 insertions(+), 1 deletion(-) > > > > > > diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c > > > index 513c357..9e690ae 100644 > > > --- a/fs/hfsplus/super.c > > > +++ b/fs/hfsplus/super.c > > > @@ -524,8 +524,10 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) > > > goto out_put_root; > > > if (!hfs_brec_read(&fd, &entry, sizeof(entry))) { > > > hfs_find_exit(&fd); > > > - if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) > > > + if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) { > > > + err = -EINVAL; > > > goto out_put_root; > > > + } > > > inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id)); > > > if (IS_ERR(inode)) { > > > err = PTR_ERR(inode); > > > -- > > > 1.8.3.1 > > > > > > > > > > I sent this same patch some time ago: > > > > https://www.spinics.net/lists/linux-fsdevel/msg125241.html > > > > This syzbot report did not reach me, though. I don't know why. > > > Oh, I didn't notice that you already wrote that patch. > Anyway, whom to ask for merge? Al Viro? Andrew Morton? I think Andrew Morton, but only one of my patches for hfsplus has been picked up so far, so I can't tell you for sure. Al Viro wasn't happy with this patchset and thought it was better to let ->put_super() handle the cleanup. I made a second version but I don't think he had the time to look at it yet. ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] hfsplus: don't return 0 when fill_super() failed 2018-05-19 23:25 ` Ernesto A. Fernández @ 2018-05-19 23:47 ` Al Viro 0 siblings, 0 replies; 5+ messages in thread From: Al Viro @ 2018-05-19 23:47 UTC (permalink / raw) To: Ernesto A. Fernández Cc: Tetsuo Handa, akpm, syzkaller-bugs, syzbot+01ffaf5d9568dd1609f7, linux-fsdevel On Sat, May 19, 2018 at 08:25:04PM -0300, Ernesto A. Fern�ndez wrote: > > Oh, I didn't notice that you already wrote that patch. > > Anyway, whom to ask for merge? Al Viro? Andrew Morton? > > I think Andrew Morton, but only one of my patches for hfsplus has been > picked up so far, so I can't tell you for sure. > > Al Viro wasn't happy with this patchset and thought it was better to let > ->put_super() handle the cleanup. I made a second version but I don't > think he had the time to look at it yet. Sorry, buried under fs/aio.c review (aio-poll stuff) and assorted shite around mkdir/open-by-handle right now ;-/ I'll get to that tonight or tomorrow morning. ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] hfsplus: don't return 0 when fill_super() failed 2018-05-15 10:08 ` [PATCH] hfsplus: don't return 0 when fill_super() failed Tetsuo Handa [not found] ` <20180515164221.57cbosgvu6ahslon@eaf> @ 2018-06-21 1:45 ` Ernesto A. Fernández 1 sibling, 0 replies; 5+ messages in thread From: Ernesto A. Fernández @ 2018-06-21 1:45 UTC (permalink / raw) To: Tetsuo Handa Cc: syzbot, syzkaller-bugs, viro, linux-fsdevel, linux-kernel, akpm On Tue, May 15, 2018 at 07:08:24PM +0900, Tetsuo Handa wrote: > From f78a5fe168290cb9e009f4d907d04b5bfe277831 Mon Sep 17 00:00:00 2001 > From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> > Date: Tue, 15 May 2018 11:38:38 +0900 > Subject: [PATCH] hfsplus: don't return 0 when fill_super() failed > > syzbot is reporting NULL pointer dereference at mount_fs() [1]. > This is because hfsplus_fill_super() is by error returning 0 when > hfsplus_fill_super() detected invalid filesystem image, and mount_bdev() > is returning NULL because dget(s->s_root) == NULL if s->s_root == NULL, > and mount_fs() is accessing root->d_sb because IS_ERR(root) == false > if root == NULL. Fix this by returning -EINVAL when hfsplus_fill_super() > detected invalid filesystem image. > > [1] https://syzkaller.appspot.com/bug?id=21acb6850cecbc960c927229e597158cf35f33d0 > > Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> > Reported-by: syzbot <syzbot+01ffaf5d9568dd1609f7@syzkaller.appspotmail.com> > Cc: Al Viro <viro@zeniv.linux.org.uk> It's been too long. I think I should give up on my patch. Maybe a review can help your version get merged. Reviewed-by: Ernesto A. Fernández <ernesto.mnd.fernandez@gmail.com> > --- > fs/hfsplus/super.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c > index 513c357..9e690ae 100644 > --- a/fs/hfsplus/super.c > +++ b/fs/hfsplus/super.c > @@ -524,8 +524,10 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) > goto out_put_root; > if (!hfs_brec_read(&fd, &entry, sizeof(entry))) { > hfs_find_exit(&fd); > - if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) > + if (entry.type != cpu_to_be16(HFSPLUS_FOLDER)) { > + err = -EINVAL; > goto out_put_root; > + } > inode = hfsplus_iget(sb, be32_to_cpu(entry.folder.id)); > if (IS_ERR(inode)) { > err = PTR_ERR(inode); > -- > 1.8.3.1 > > ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2018-06-21 1:46 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-04-05 2:02 general protection fault in mount_fs syzbot
2018-05-15 10:08 ` [PATCH] hfsplus: don't return 0 when fill_super() failed Tetsuo Handa
[not found] ` <20180515164221.57cbosgvu6ahslon@eaf>
[not found] ` <201805192255.CAD48427.HLtFMOFVOSOQJF@I-love.SAKURA.ne.jp>
2018-05-19 23:25 ` Ernesto A. Fernández
2018-05-19 23:47 ` Al Viro
2018-06-21 1:45 ` Ernesto A. Fernández
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