diff options
| author | Andrey Mirkin <amirkin@openvz.org> | 2006-12-06 20:31:35 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-07 08:39:20 -0800 |
| commit | 822191a2fa1584a29c3224ab328507adcaeac1ab (patch) | |
| tree | 833b6e7d88fc49bf430826db26f75b4877593a15 /fs/compat.c | |
| parent | a1e85378ba50694cf8f27b190c7e16d7c8dad276 (diff) | |
| download | lwn-822191a2fa1584a29c3224ab328507adcaeac1ab.tar.gz lwn-822191a2fa1584a29c3224ab328507adcaeac1ab.zip | |
[PATCH] skip data conversion in compat_sys_mount when data_page is NULL
OpenVZ Linux kernel team has found a problem with mounting in compat mode.
Simple command "mount -t smbfs ..." on Fedora Core 5 distro in 32-bit mode
leads to oops:
Unable to handle kernel NULL pointer dereference at 0000000000000000 RIP: compat_sys_mount+0xd6/0x290
Process mount (pid: 14656, veid=300, threadinfo ffff810034d30000, task ffff810034c86bc0)
Call Trace: ia32_sysret+0x0/0xa
The problem is that data_page pointer can be NULL, so we should skip data
conversion in this case.
Signed-off-by: Andrey Mirkin <amirkin@openvz.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs/compat.c')
| -rw-r--r-- | fs/compat.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/compat.c b/fs/compat.c index 06dad665b88f..7aef5412f49c 100644 --- a/fs/compat.c +++ b/fs/compat.c @@ -871,7 +871,7 @@ asmlinkage long compat_sys_mount(char __user * dev_name, char __user * dir_name, retval = -EINVAL; - if (type_page) { + if (type_page && data_page) { if (!strcmp((char *)type_page, SMBFS_NAME)) { do_smb_super_data_conv((void *)data_page); } else if (!strcmp((char *)type_page, NCPFS_NAME)) { |