Searched hist:"910 cd32e552ea09caa89cdbe328e468979b030dd" (Results 1 – 3 of 3) sorted by relevance
/linux/arch/parisc/include/asm/ |
H A D | syscall.h | diff 910cd32e552ea09caa89cdbe328e468979b030dd Wed Mar 30 14:14:31 CEST 2016 Helge Deller <deller@gmx.de> parisc: Fix and enable seccomp filter support
The seccomp filter support requires careful handling of task registers. This includes reloading of the return value (%r28) and proper syscall exit if secure_computing() returned -1.
Additionally we need to sign-extend the syscall number from signed 32bit to signed 64bit in do_syscall_trace_enter() since the ptrace interface only allows storing 32bit values in compat mode.
Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org # v4.5
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/linux/arch/parisc/kernel/ |
H A D | ptrace.c | diff b7dc5a071ddf69c0350396b203cba32fe5bab510 Sat Feb 16 14:10:39 CET 2019 Dmitry V. Levin <ldv@altlinux.org> parisc: Fix ptrace syscall number modification
Commit 910cd32e552e ("parisc: Fix and enable seccomp filter support") introduced a regression in ptrace-based syscall tampering: when tracer changes syscall number to -1, the kernel fails to initialize %r28 with -ENOSYS and subsequently fails to return the error code of the failed syscall to userspace.
This erroneous behaviour could be observed with a simple strace syscall fault injection command which is expected to print something like this:
$ strace -a0 -ewrite -einject=write:error=enospc echo hello write(1, "hello\n", 6) = -1 ENOSPC (No space left on device) (INJECTED) write(2, "echo: ", 6) = -1 ENOSPC (No space left on device) (INJECTED) write(2, "write error", 11) = -1 ENOSPC (No space left on device) (INJECTED) write(2, "\n", 1) = -1 ENOSPC (No space left on device) (INJECTED) +++ exited with 1 +++
After commit 910cd32e552ea09caa89cdbe328e468979b030dd it loops printing something like this instead:
write(1, "hello\n", 6../strace: Failed to tamper with process 12345: unexpectedly got no error (return value 0, error 0) ) = 0 (INJECTED)
This bug was found by strace test suite.
Fixes: 910cd32e552e ("parisc: Fix and enable seccomp filter support") Cc: stable@vger.kernel.org # v4.5+ Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Tested-by: Helge Deller <deller@gmx.de> Signed-off-by: Helge Deller <deller@gmx.de> diff 910cd32e552ea09caa89cdbe328e468979b030dd Wed Mar 30 14:14:31 CEST 2016 Helge Deller <deller@gmx.de> parisc: Fix and enable seccomp filter support
The seccomp filter support requires careful handling of task registers. This includes reloading of the return value (%r28) and proper syscall exit if secure_computing() returned -1.
Additionally we need to sign-extend the syscall number from signed 32bit to signed 64bit in do_syscall_trace_enter() since the ptrace interface only allows storing 32bit values in compat mode.
Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org # v4.5
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H A D | syscall.S | diff 910cd32e552ea09caa89cdbe328e468979b030dd Wed Mar 30 14:14:31 CEST 2016 Helge Deller <deller@gmx.de> parisc: Fix and enable seccomp filter support
The seccomp filter support requires careful handling of task registers. This includes reloading of the return value (%r28) and proper syscall exit if secure_computing() returned -1.
Additionally we need to sign-extend the syscall number from signed 32bit to signed 64bit in do_syscall_trace_enter() since the ptrace interface only allows storing 32bit values in compat mode.
Signed-off-by: Helge Deller <deller@gmx.de> Cc: stable@vger.kernel.org # v4.5
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