This is a note to let you know that I've just added the patch titled tracing: probeevent: Fix to support minus offset from symbol to the 4.15-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-probeevent-fix-to-support-minus-offset-from-symbol.patch and it can be found in the queue-4.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c5d343b6b7badd1f5fe0873eff2e8d63a193e732 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Date: Sat, 17 Mar 2018 21:38:10 +0900 Subject: tracing: probeevent: Fix to support minus offset from symbol From: Masami Hiramatsu <mhiramat@xxxxxxxxxx> commit c5d343b6b7badd1f5fe0873eff2e8d63a193e732 upstream. In Documentation/trace/kprobetrace.txt, it says @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) However, the parser doesn't parse minus offset correctly, since commit 2fba0c8867af ("tracing/kprobes: Fix probe offset to be unsigned") drops minus ("-") offset support for kprobe probe address usage. This fixes the traceprobe_split_symbol_offset() to parse minus offset again with checking the offset range, and add a minus offset check in kprobe probe address usage. Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Tom Zanussi <tom.zanussi@xxxxxxxxxxxxxxx> Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Cc: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Fixes: 2fba0c8867af ("tracing/kprobes: Fix probe offset to be unsigned") Acked-by: Namhyung Kim <namhyung@xxxxxxxxxx> Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/trace/trace_kprobe.c | 4 ++-- kernel/trace/trace_probe.c | 8 +++----- kernel/trace/trace_probe.h | 2 +- 3 files changed, 6 insertions(+), 8 deletions(-) --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -635,7 +635,7 @@ static int create_trace_kprobe(int argc, char *symbol = NULL, *event = NULL, *group = NULL; int maxactive = 0; char *arg; - unsigned long offset = 0; + long offset = 0; void *addr = NULL; char buf[MAX_EVENT_NAME_LEN]; @@ -723,7 +723,7 @@ static int create_trace_kprobe(int argc, symbol = argv[1]; /* TODO: support .init module functions */ ret = traceprobe_split_symbol_offset(symbol, &offset); - if (ret) { + if (ret || offset < 0 || offset > UINT_MAX) { pr_info("Failed to parse either an address or a symbol.\n"); return ret; } --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -320,7 +320,7 @@ static fetch_func_t get_fetch_size_funct } /* Split symbol and offset. */ -int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset) +int traceprobe_split_symbol_offset(char *symbol, long *offset) { char *tmp; int ret; @@ -328,13 +328,11 @@ int traceprobe_split_symbol_offset(char if (!offset) return -EINVAL; - tmp = strchr(symbol, '+'); + tmp = strpbrk(symbol, "+-"); if (tmp) { - /* skip sign because kstrtoul doesn't accept '+' */ - ret = kstrtoul(tmp + 1, 0, offset); + ret = kstrtol(tmp, 0, offset); if (ret) return ret; - *tmp = '\0'; } else *offset = 0; --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -353,7 +353,7 @@ extern int traceprobe_conflict_field_nam extern void traceprobe_update_arg(struct probe_arg *arg); extern void traceprobe_free_probe_arg(struct probe_arg *arg); -extern int traceprobe_split_symbol_offset(char *symbol, unsigned long *offset); +extern int traceprobe_split_symbol_offset(char *symbol, long *offset); /* Sum up total data length for dynamic arraies (strings) */ static nokprobe_inline int Patches currently in stable-queue which might be from mhiramat@xxxxxxxxxx are queue-4.15/tracing-probeevent-fix-to-support-minus-offset-from-symbol.patch