The following commit has been merged into the perf/urgent branch of tip: Commit-ID: d74b181a028bb5a468f0c609553eff6a8fdf4887 Gitweb: https://git.kernel.org/tip/d74b181a028bb5a468f0c609553eff6a8fdf4887 Author: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> AuthorDate: Tue, 24 Mar 2020 08:03:19 +01:00 Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> CommitterDate: Tue, 24 Mar 2020 10:36:00 -03:00 perf cpumap: Fix snprintf overflow check 'snprintf' returns the number of characters which would be generated for the given input. If the returned value is *greater than* or equal to the buffer size, it means that the output has been truncated. Fix the overflow test accordingly. Fixes: 7780c25bae59f ("perf tools: Allow ability to map cpus to nodes easily") Fixes: 92a7e1278005b ("perf cpumap: Add cpu__max_present_cpu()") Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx> Suggested-by: David Laight <David.Laight@xxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Don Zickus <dzickus@xxxxxxxxxx> Cc: He Zhe <zhe.he@xxxxxxxxxxxxx> Cc: Jan Stancek <jstancek@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: kernel-janitors@xxxxxxxxxxxxxxx Link: http://lore.kernel.org/lkml/20200324070319.10901-1-christophe.jaillet@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> --- tools/perf/util/cpumap.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c index 983b738..dc5c5e6 100644 --- a/tools/perf/util/cpumap.c +++ b/tools/perf/util/cpumap.c @@ -317,7 +317,7 @@ static void set_max_cpu_num(void) /* get the highest possible cpu number for a sparse allocation */ ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/possible", mnt); - if (ret == PATH_MAX) { + if (ret >= PATH_MAX) { pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX); goto out; } @@ -328,7 +328,7 @@ static void set_max_cpu_num(void) /* get the highest present cpu number for a sparse allocation */ ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/present", mnt); - if (ret == PATH_MAX) { + if (ret >= PATH_MAX) { pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX); goto out; } @@ -356,7 +356,7 @@ static void set_max_node_num(void) /* get the highest possible cpu number for a sparse allocation */ ret = snprintf(path, PATH_MAX, "%s/devices/system/node/possible", mnt); - if (ret == PATH_MAX) { + if (ret >= PATH_MAX) { pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX); goto out; } @@ -441,7 +441,7 @@ int cpu__setup_cpunode_map(void) return 0; n = snprintf(path, PATH_MAX, "%s/devices/system/node", mnt); - if (n == PATH_MAX) { + if (n >= PATH_MAX) { pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX); return -1; } @@ -456,7 +456,7 @@ int cpu__setup_cpunode_map(void) continue; n = snprintf(buf, PATH_MAX, "%s/%s", path, dent1->d_name); - if (n == PATH_MAX) { + if (n >= PATH_MAX) { pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX); continue; }
