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| author | Jiri Slaby <jslaby@suse.cz> | 2012-04-13 08:31:32 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-04-13 17:54:43 (GMT) |
| commit | a2f892060f174e5f90041167ca00eb9e68badcb8 (patch) | |
| tree | daf87a58266da05e2e8a3f06538df2cfd360d3bc /drivers/parisc | |
| parent | 59d59b0600e541b4e94b891148c92f2e2d18f7c0 (diff) | |
| download | linux-fsl-qoriq-a2f892060f174e5f90041167ca00eb9e68badcb8.tar.xz | |
TTY: hvc, fix TTY refcounting
A -next commit "TTY: HVC, use tty from tty_port" switched the driver
to use tty_port helper for tty refcounting. But it omitted to remove
manual tty refcounting from open, close and hangup. So now we are
getting random crashes caused by use-after-free:
Unable to handle kernel paging request for data at address 0xc0000003f9d550
Faulting instruction address: 0xc0000000001b7f40
Oops: Kernel access of bad area, sig: 11 [#1]
...
NIP: c0000000001b7f40 LR: c0000000001b7f14 CTR: c0000000000e04f0
...
NIP [c0000000001b7f40] .__kmalloc+0x70/0x230
LR [c0000000001b7f14] .__kmalloc+0x44/0x230
Call Trace:
[c0000003f68bf930] [c0000003f68bf9b0] 0xc0000003f68bf9b0 (unreliable)
[c0000003f68bf9e0] [c0000000001e5424] .alloc_fdmem+0x24/0x70
[c0000003f68bfa60] [c0000000001e54f8] .alloc_fdtable+0x88/0x130
[c0000003f68bfaf0] [c0000000001e5924] .dup_fd+0x384/0x450
[c0000003f68bfbd0] [c00000000009a310] .copy_process+0x880/0x11d0
[c0000003f68bfcd0] [c00000000009aee0] .do_fork+0x70/0x400
[c0000003f68bfdc0] [c0000000000141c4] .sys_clone+0x54/0x70
[c0000003f68bfe30] [c000000000009aa0] .ppc_clone+0x8/0xc
Fix that by complete removal of tty_kref_get/put in open/close/hangup
paths.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-and-tested-by: Michael Neuling <mikey@neuling.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: ppc-dev <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/parisc')
0 files changed, 0 insertions, 0 deletions