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author | Masami Hiramatsu <mhiramat@kernel.org> | 2018-04-10 21:20:08 +0900 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-05-16 10:12:35 +0200 |
commit | 500a846cd788e925aad4f2c5b0a54c678a9105ce (patch) | |
tree | 14e4a630fb129a691e82bd7f85119ff84220ec7e | |
parent | 8577c7a3191dd08b9e5a246630cdd628f248a94f (diff) |
tracing/uprobe_event: Fix strncpy corner case
commit 50268a3d266ecfdd6c5873d62b2758d9732fc598 upstream.
Fix string fetch function to terminate with NUL.
It is OK to drop the rest of string.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org
Cc: 范龙飞 <long7573@126.com>
Fixes: 5baaa59ef09e ("tracing/probes: Implement 'memory' fetch method for uprobes")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | kernel/trace/trace_uprobe.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index fff97dc0b70f..67a52bbbe48d 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -152,6 +152,8 @@ static void FETCH_FUNC_NAME(memory, string)(struct pt_regs *regs, return; ret = strncpy_from_user(dst, src, maxlen); + if (ret == maxlen) + dst[--ret] = '\0'; if (ret < 0) { /* Failed to fetch string */ ((u8 *)get_rloc_data(dest))[0] = '\0'; |