Messages in this thread | | | Date | Sun, 26 Oct 2008 01:23:36 +0100 | From | Al Viro <> | Subject | Re: v2.6.28-rc1: readlink /proc/*/exe returns uninitialized data to userspace |
| |
On Sat, Oct 25, 2008 at 07:14:21PM +0200, Vegard Nossum wrote: > It was discovered by kmemcheck: > > WARNING: kmemcheck: Caught 32-bit read from uninitialized memory (f6a109e4) > 64000000ad4eaddeffffffffffffffff000000000200000000000000c0838ff8 > i i u u u u u u u u u u u u u u u u u u u u u u u u u u u u u u > ^ > > Pid: 21511, comm: readlink Not tainted (2.6.28-rc1 #58) 945P-A > EIP: 0060:[<c04f988d>] EFLAGS: 00000296 CPU: 0 > EIP is at __d_path+0x8d/0x1c0 > EAX: 0000000e EBX: d7ba0fe7 ECX: 00000001 EDX: f68b0b40 > ESI: f6a109e4 EDI: d7ba0fef EBP: e58c3f28 ESP: c2569c08 > DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 > CR0: 8005003b CR2: f6c1d704 CR3: 31fc7000 CR4: 00000650 > DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 > DR6: ffff4ff0 DR7: 00000400 > [<c04fa4b0>] d_path+0xb0/0xd0 > [<c052c37c>] proc_pid_readlink+0x6c/0xc0 > [<c04eda34>] sys_readlinkat+0x94/0xa0 > [<c04eda67>] sys_readlink+0x27/0x30 > [<c0422f83>] sysenter_do_call+0x12/0x3f > [<ffffffff>] 0xffffffff > > Line numbers are these (as of commit > e013e13bf605b9e6b702adffbe2853cfc60e7806 in Linus's tree): > > $ addr2line -e vmlinux -i c04f988d c04fa4b0 c052c37c c04eda34 c04eda67 > fs/dcache.c:1895 > fs/dcache.c:1901 > fs/dcache.c:1957 > fs/dcache.c:2016 > fs/proc/base.c:1347 > fs/proc/base.c:1374 > fs/stat.c:312 > fs/stat.c:325 > > I couldn't immediately figure out who/what to blame, please Cc in > right direction if you think you know it :-) > > (For the record: This didn't show up in 2.6.27-rc with the same > version of LTP, so it seems to be a recent regression.)
Very odd. Do you see that for any other processes? Where does /sbin/udevd live on your box? BTW, .config might be useful here...
Can you reproduce that on e.g. amd64 and/or without kmemcheck?
| |