lkml.org 
[lkml]   [2005]   [Nov]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] 3/3 Generic sys_rt_sigsuspend
From
Date
On Tue, 2005-11-29 at 10:53 -0500, Daniel Jacobowitz wrote:
> And, crazy coincidence, I think this will fix the recently reported
> ptrace attach bug. Right now if you ptrace a process stuck in
> sigsuspend, you can't easily force it to return to userspace.
> I'll test that if these patches are merged.

That seems to be true. What I get with my patches is...

# strace -p `pidof sigsusptest`
Process 1954 attached - interrupt to quit
rt_sigsuspend([]) = ? ERESTARTNOHAND (To be restarted)
--- SIGALRM (Alarm clock) @ 0 (0) ---
sigreturn() = ? (mask now [])
fstat64(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(4, 64), ...}) = 0
ioctl(1, TCGETS, {B115200 opost isig icanon echo ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x3001f000
write(1, "r is -1\n", 8) = 8
munmap(0x3001f000, 4096) = 0
exit_group(8) = ?
Process 1954 detached

... whereas without them I get not only a failure to attach, until
there's a signal, but an unexplained SIGSEGV too...

# strace -p `pidof sigsusptest`
Process 3105 attached - interrupt to quit
--- SIGALRM (Alarm clock) @ 0 (0) ---
rt_sigsuspend([]) = 14
rt_sigsuspend([] <unfinished ...>
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
Process 3105 detached

--
dwmw2


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-11-29 17:12    [W:0.070 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site