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| author | kmixter@chromium.org <kmixter@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2011-06-21 04:21:06 +0000 |
|---|---|---|
| committer | kmixter@chromium.org <kmixter@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2011-06-21 04:21:06 +0000 |
| commit | cb7d53e31de7cb61b190ab56f6136dd44a55aee9 (patch) | |
| tree | 8df5e007f3eb983e2b6ab6ab0d088d893e53cf81 /base | |
| parent | d01576c153e5a60a7a76340220bcb096180993b0 (diff) | |
| download | chromium_src-cb7d53e31de7cb61b190ab56f6136dd44a55aee9.zip chromium_src-cb7d53e31de7cb61b190ab56f6136dd44a55aee9.tar.gz chromium_src-cb7d53e31de7cb61b190ab56f6136dd44a55aee9.tar.bz2 | |
Always search TIDs for the crashing processes.
Kernels newer than 2.6.32 support TID and PID namespacing where
processes' view of their TIDs and PIDs are not globally unique or
externally meaningful. We have workarounds to find the TID and PID of
the crashing process from outside in the browser process. However, we
were only assuming TID namespacing was happening if PID namespacing
was enabled and the kernel had a bug that was fixed since 2.6.38.
This change causes us to always treat the TID as subject to
namespacing. Our trick to find the TID relies on a procfs feature
added in 2008. We assume if that feature is not yet present that
the TID translation is not necessary.
This fixes the bug where all crashes of non-browser processes on Linux
2.6.38+ (Chrome OS r13+) are unusable (result in
UnspecifiedStackSignature).
BUG=chromium-os:15462
TEST=Do about:crash on 2.6.38 kernel and verify proper tid listed in
MDException block
Review URL: http://codereview.chromium.org/7190019
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@89795 0039d316-1c4b-4281-b951-d872f2087c98
Diffstat (limited to 'base')
| -rw-r--r-- | base/linux_util.cc | 9 | ||||
| -rw-r--r-- | base/linux_util.h | 6 |
2 files changed, 12 insertions, 3 deletions
diff --git a/base/linux_util.cc b/base/linux_util.cc index 2f9f862..a24f311 100644 --- a/base/linux_util.cc +++ b/base/linux_util.cc @@ -252,9 +252,14 @@ bool FindProcessHoldingSocket(pid_t* pid_out, ino_t socket_inode) { return already_found; } -pid_t FindThreadIDWithSyscall(pid_t pid, const std::string& expected_data) { +pid_t FindThreadIDWithSyscall(pid_t pid, const std::string& expected_data, + bool* syscall_supported) { char buf[256]; snprintf(buf, sizeof(buf), "/proc/%d/task", pid); + + if (syscall_supported != NULL) + *syscall_supported = false; + DIR* task = opendir(buf); if (!task) { LOG(WARNING) << "Cannot open " << buf; @@ -280,6 +285,8 @@ pid_t FindThreadIDWithSyscall(pid_t pid, const std::string& expected_data) { int fd = open(buf, O_RDONLY); if (fd < 0) continue; + if (syscall_supported != NULL) + *syscall_supported = true; bool read_ret = file_util::ReadFromFD(fd, syscall_data.get(), expected_data.length()); close(fd); diff --git a/base/linux_util.h b/base/linux_util.h index de597db..d33cb88 100644 --- a/base/linux_util.h +++ b/base/linux_util.h @@ -37,9 +37,11 @@ BASE_API bool FindProcessHoldingSocket(pid_t* pid_out, ino_t socket_inode); // For a given process |pid|, look through all its threads and find the first // thread with /proc/[pid]/task/[thread_id]/syscall whose first N bytes matches // |expected_data|, where N is the length of |expected_data|. -// Returns the thread id or -1 on error. +// Returns the thread id or -1 on error. If |syscall_supported| is +// set to false the kernel does not support syscall in procfs. BASE_API pid_t FindThreadIDWithSyscall(pid_t pid, - const std::string& expected_data); + const std::string& expected_data, + bool* syscall_supported); } // namespace base |