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| author | Al Viro <viro@ZenIV.linux.org.uk> | 2012-12-09 07:16:14 +0100 |
|---|---|---|
| committer | Helge Deller <deller@gmx.de> | 2013-02-20 22:51:11 +0100 |
| commit | 52ab532ea76d30b7e7a7b98021e2e873e83029a5 (patch) | |
| tree | fa11ff7efd4251743d444bef649bfa068e702237 /arch/parisc | |
| parent | parisc: always detect multiple physical ranges (diff) | |
| download | linux-52ab532ea76d30b7e7a7b98021e2e873e83029a5.tar.xz linux-52ab532ea76d30b7e7a7b98021e2e873e83029a5.zip | |
parisc: fix ptrace breakage
1) PTRACE_SYSCALL doesn't work for 64bit process on parisc64.
Compat syscall table is used instead of 64bit one. IMO we should either
refuse to allow PTRACE_SYSCALL for 64bit processes or duplicate the
logics choosing the right syscall table into .Ltracesys.
2) if you have let the tracee run with PTRACE_SYSCALL and
it had stopped, you can use PTRACE_POKEUSR to modify syscall number
(r20) and arguments 1--4 (r26--r23). Modifications will have effect.
However, modifying arguments 5 and 6 (r22 and r21 resp.) works only
when process (32bit one) runs on 64bit host - on 32bit one it has no
effect. AFAICS, the diff below should fix that one.
Signed-off-by: Al Viro <viro@ZenIV.linux.org.uk>
Tested-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>
Diffstat (limited to 'arch/parisc')
| -rw-r--r-- | arch/parisc/kernel/syscall.S | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/arch/parisc/kernel/syscall.S b/arch/parisc/kernel/syscall.S index 86742df0b194..5e055240f00b 100644 --- a/arch/parisc/kernel/syscall.S +++ b/arch/parisc/kernel/syscall.S @@ -309,10 +309,13 @@ tracesys_next: LDREG TASK_PT_GR25(%r1), %r25 LDREG TASK_PT_GR24(%r1), %r24 LDREG TASK_PT_GR23(%r1), %r23 -#ifdef CONFIG_64BIT LDREG TASK_PT_GR22(%r1), %r22 LDREG TASK_PT_GR21(%r1), %r21 +#ifdef CONFIG_64BIT ldo -16(%r30),%r29 /* Reference param save area */ +#else + stw %r22, -52(%r30) /* 5th argument */ + stw %r21, -56(%r30) /* 6th argument */ #endif comiclr,>>= __NR_Linux_syscalls, %r20, %r0 |