diff options
| author | Jeff Dike <jdike@addtoit.com> | 2007-01-30 14:36:17 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-01-30 16:01:35 -0800 |
| commit | 3896625d0badd53dbc34d584861a36ba7eb4613f (patch) | |
| tree | 35af106b8356634a0e804341b8eb0a90b588df41 | |
| parent | 99abaf51e25f7d4ac2081e5cdc1f01baa0543514 (diff) | |
| download | lwn-3896625d0badd53dbc34d584861a36ba7eb4613f.tar.gz lwn-3896625d0badd53dbc34d584861a36ba7eb4613f.zip | |
[PATCH] uml: fix signal frame alignment
Use the same signal frame alignment calculations as the underlying
architecture. x86_64 appeared to do this, but the "- 8" was really
subtracting 8 * sizeof(struct rt_sigframe) rather than 8 bytes.
UML/i386 might have been OK, but I changed the calculation to match
i386 just to be sure.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: <stable@kernel.org>
Cc: Adrian Bunk <bunk@stusta.de>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Acked-by: Antoine Martin <antoine@nagafix.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | arch/um/sys-i386/signal.c | 3 | ||||
| -rw-r--r-- | arch/um/sys-x86_64/signal.c | 5 |
2 files changed, 5 insertions, 3 deletions
diff --git a/arch/um/sys-i386/signal.c b/arch/um/sys-i386/signal.c index 0709fc6670c2..3f6acd667717 100644 --- a/arch/um/sys-i386/signal.c +++ b/arch/um/sys-i386/signal.c @@ -219,7 +219,8 @@ int setup_signal_stack_sc(unsigned long stack_top, int sig, unsigned long save_sp = PT_REGS_SP(regs); int err = 0; - stack_top &= -8UL; + /* This is the same calculation as i386 - ((sp + 4) & 15) == 0 */ + stack_top = ((stack_top + 4) & -16UL) - 4; frame = (struct sigframe __user *) stack_top - 1; if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) return 1; diff --git a/arch/um/sys-x86_64/signal.c b/arch/um/sys-x86_64/signal.c index 9edf114faf79..af2f017617b4 100644 --- a/arch/um/sys-x86_64/signal.c +++ b/arch/um/sys-x86_64/signal.c @@ -191,8 +191,9 @@ int setup_signal_stack_si(unsigned long stack_top, int sig, struct task_struct *me = current; frame = (struct rt_sigframe __user *) - round_down(stack_top - sizeof(struct rt_sigframe), 16) - 8; - frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128); + round_down(stack_top - sizeof(struct rt_sigframe), 16); + /* Subtract 128 for a red zone and 8 for proper alignment */ + frame = (struct rt_sigframe __user *) ((unsigned long) frame - 128 - 8); if (!access_ok(VERIFY_WRITE, fp, sizeof(struct _fpstate))) goto out; |