This is a note to let you know that I've just added the patch titled tracing: Fix possible NULL pointer dereferences to the 3.0-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: tracing-fix-possible-null-pointer-dereferences.patch and it can be found in the queue-3.0 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From lizefan@xxxxxxxxxx Mon Jun 10 14:16:36 2013 From: Li Zefan <lizefan@xxxxxxxxxx> Date: Fri, 7 Jun 2013 17:00:33 +0800 Subject: tracing: Fix possible NULL pointer dereferences To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx>, Frederic Weisbecker <fweisbec@xxxxxxxxx>, Steven Rostedt <rostedt@xxxxxxxxxxx>, Ingo Molnar <mingo@xxxxxxxxxx>, LKML <linux-kernel@xxxxxxxxxxxxxxx>, stable <stable@xxxxxxxxxxxxxxx> Message-ID: <51B1A131.9090206@xxxxxxxxxx> From: Namhyung Kim <namhyung.kim@xxxxxxx> commit 6a76f8c0ab19f215af2a3442870eeb5f0e81998d upstream. Currently set_ftrace_pid and set_graph_function files use seq_lseek for their fops. However seq_open() is called only for FMODE_READ in the fops->open() so that if an user tries to seek one of those file when she open it for writing, it sees NULL seq_file and then panic. It can be easily reproduced with following command: $ cd /sys/kernel/debug/tracing $ echo 1234 | sudo tee -a set_ftrace_pid In this example, GNU coreutils' tee opens the file with fopen(, "a") and then the fopen() internally calls lseek(). Link: http://lkml.kernel.org/r/1365663302-2170-1-git-send-email-namhyung@xxxxxxxxxx Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Namhyung Kim <namhyung.kim@xxxxxxx> Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> [ lizf: adjust context ] Signed-off-by: Li Zefan <lizefan@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/trace/ftrace.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2300,7 +2300,7 @@ ftrace_notrace_open(struct inode *inode, } static loff_t -ftrace_regex_lseek(struct file *file, loff_t offset, int origin) +ftrace_filter_lseek(struct file *file, loff_t offset, int origin) { loff_t ret; @@ -3118,7 +3118,7 @@ static const struct file_operations ftra .open = ftrace_filter_open, .read = seq_read, .write = ftrace_filter_write, - .llseek = ftrace_regex_lseek, + .llseek = ftrace_filter_lseek, .release = ftrace_regex_release, }; @@ -3126,7 +3126,7 @@ static const struct file_operations ftra .open = ftrace_notrace_open, .read = seq_read, .write = ftrace_notrace_write, - .llseek = ftrace_regex_lseek, + .llseek = ftrace_filter_lseek, .release = ftrace_regex_release, }; @@ -3335,8 +3335,8 @@ static const struct file_operations ftra .open = ftrace_graph_open, .read = seq_read, .write = ftrace_graph_write, + .llseek = ftrace_filter_lseek, .release = ftrace_graph_release, - .llseek = seq_lseek, }; #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ @@ -3822,7 +3822,7 @@ static const struct file_operations ftra .open = ftrace_pid_open, .write = ftrace_pid_write, .read = seq_read, - .llseek = seq_lseek, + .llseek = ftrace_filter_lseek, .release = ftrace_pid_release, }; Patches currently in stable-queue which might be from lizefan@xxxxxxxxxx are queue-3.0/tracing-fix-possible-null-pointer-dereferences.patch queue-3.0/ftrace-move-ftrace_filter_lseek-out-of-config_dynamic_ftrace-section.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html