From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- tools/perf/Documentation/perf-data.txt | 82 ++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 tools/perf/Documentation/perf-data.txt (limited to 'tools/perf/Documentation/perf-data.txt') diff --git a/tools/perf/Documentation/perf-data.txt b/tools/perf/Documentation/perf-data.txt new file mode 100644 index 000000000..20f178d61 --- /dev/null +++ b/tools/perf/Documentation/perf-data.txt @@ -0,0 +1,82 @@ +perf-data(1) +============ + +NAME +---- +perf-data - Data file related processing + +SYNOPSIS +-------- +[verse] +'perf data' [] []", + +DESCRIPTION +----------- +Data file related processing. + +COMMANDS +-------- +convert:: + Converts perf data file into another format. + It's possible to set data-convert debug variable to get debug messages from conversion, + like: + perf --debug data-convert data convert ... + +OPTIONS for 'convert' +--------------------- +--to-ctf:: + Triggers the CTF conversion, specify the path of CTF data directory. + +--to-json:: + Triggers JSON conversion. Specify the JSON filename to output. + +--tod:: + Convert time to wall clock time. + +-i:: + Specify input perf data file path. + +-f:: +--force:: + Don't complain, do it. + +--time:: + Only convert samples within given time window: ,. Times + have the format seconds.nanoseconds. If start is not given (i.e. time + string is ',x.y') then analysis starts at the beginning of the file. If + stop time is not given (i.e. time string is 'x.y,') then analysis goes + to end of file. Multiple ranges can be separated by spaces, which + requires the argument to be quoted e.g. --time "1234.567,1234.789 1235," + + Also support time percent with multiple time ranges. Time string is + 'a%/n,b%/m,...' or 'a%-b%,c%-%d,...'. + + For example: + Select the second 10% time slice: + + perf data convert --to-json out.json --time 10%/2 + + Select from 0% to 10% time slice: + + perf data convert --to-json out.json --time 0%-10% + + Select the first and second 10% time slices: + + perf data convert --to-json out.json --time 10%/1,10%/2 + + Select from 0% to 10% and 30% to 40% slices: + + perf data convert --to-json out.json --time 0%-10%,30%-40% + +-v:: +--verbose:: + Be more verbose (show counter open errors, etc). + +--all:: + Convert all events, including non-sample events (comm, fork, ...), to output. + Default is off, only convert samples. + +SEE ALSO +-------- +linkperf:perf[1] +[1] Common Trace Format - http://www.efficios.com/ctf -- cgit v1.3.1