https://github.com/torvalds/linux
Revision 6342adcaa683c2b705c24ed201dc11b35854c88d authored by Gabriel Krisman Bertazi on 03 February 2021, 18:00:48 UTC, committed by Thomas Gleixner on 05 February 2021, 23:21:42 UTC
Commit 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") introduced a bug on architectures using the generic syscall entry code, in which processes stopped by PTRACE_SYSCALL do not trap on syscall return after receiving a TIF_SINGLESTEP. The reason is that the meaning of TIF_SINGLESTEP flag is overloaded to cause the trap after a system call is executed, but since the above commit, the syscall call handler only checks for the SYSCALL_WORK flags on the exit work. Split the meaning of TIF_SINGLESTEP such that it only means single-step mode, and create a new type of SYSCALL_WORK to request a trap immediately after a syscall in single-step mode. In the current implementation, the SYSCALL_WORK flag shadows the TIF_SINGLESTEP flag for simplicity. Update x86 to flip this bit when a tracer enables single stepping. Fixes: 299155244770 ("entry: Drop usage of TIF flags in the generic syscall code") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kyle Huey <me@kylehuey.com> Link: https://lore.kernel.org/r/87h7mtc9pr.fsf_-_@collabora.com
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Tip revision: 6342adcaa683c2b705c24ed201dc11b35854c88d authored by Gabriel Krisman Bertazi on 03 February 2021, 18:00:48 UTC
entry: Ensure trap after single-step on system call return
entry: Ensure trap after single-step on system call return
Tip revision: 6342adc
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arch | ||
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certs | ||
crypto | ||
drivers | ||
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include | ||
init | ||
ipc | ||
kernel | ||
lib | ||
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net | ||
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.clang-format | -rw-r--r-- | 16.3 KB |
.cocciconfig | -rw-r--r-- | 59 bytes |
.get_maintainer.ignore | -rw-r--r-- | 71 bytes |
.gitattributes | -rw-r--r-- | 62 bytes |
.gitignore | -rw-r--r-- | 1.8 KB |
.mailmap | -rw-r--r-- | 18.0 KB |
COPYING | -rw-r--r-- | 496 bytes |
CREDITS | -rw-r--r-- | 98.4 KB |
Kbuild | -rw-r--r-- | 1.3 KB |
Kconfig | -rw-r--r-- | 555 bytes |
MAINTAINERS | -rw-r--r-- | 572.2 KB |
Makefile | -rw-r--r-- | 62.9 KB |
README | -rw-r--r-- | 727 bytes |
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