diff options
| author | Kees Cook <kees@kernel.org> | 2024-09-28 14:08:31 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-02-08 09:56:49 +0100 |
| commit | 4338831b831c76c9511b1f3aef64510b292da444 (patch) | |
| tree | 9c04807e21cfd60d7ed48cbc26b926813d6e5ace | |
| parent | d914acc16b5910bf9b46e2e8b441569bfe180d1b (diff) | |
coredump: Do not lock during 'comm' reporting
[ Upstream commit 200f091c95bbc4b8660636bd345805c45d6eced7 ]
The 'comm' member will always be NUL terminated, and this is not
fast-path, so we can just perform a direct memcpy during a coredump
instead of potentially deadlocking while holding the task struct lock.
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Closes: https://lore.kernel.org/all/d122ece6-3606-49de-ae4d-8da88846bef2@oracle.com
Fixes: c114e9948c2b ("coredump: Standartize and fix logging")
Tested-by: Vegard Nossum <vegard.nossum@oracle.com>
Link: https://lore.kernel.org/r/20240928210830.work.307-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | include/linux/coredump.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/coredump.h b/include/linux/coredump.h index 45e598fe3476..77e6e195d1d6 100644 --- a/include/linux/coredump.h +++ b/include/linux/coredump.h @@ -52,8 +52,8 @@ extern void do_coredump(const kernel_siginfo_t *siginfo); #define __COREDUMP_PRINTK(Level, Format, ...) \ do { \ char comm[TASK_COMM_LEN]; \ - \ - get_task_comm(comm, current); \ + /* This will always be NUL terminated. */ \ + memcpy(comm, current->comm, sizeof(comm)); \ printk_ratelimited(Level "coredump: %d(%*pE): " Format "\n", \ task_tgid_vnr(current), (int)strlen(comm), comm, ##__VA_ARGS__); \ } while (0) \ |