From 5ceb90aa667afbd0941f045073d54aea35d40f1b Mon Sep 17 00:00:00 2001 From: Ed Maste Date: Tue, 25 May 2021 14:25:18 -0400 Subject: [PATCH] elfctl: avoid touching file if no change made Suggested by: brooks Reviewed by: brooks, markj MFC after: 1 week Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D30452 (cherry picked from commit 3f2508b7f3855102abed99b846e30e728ba3d04d) --- usr.bin/elfctl/elfctl.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/usr.bin/elfctl/elfctl.c b/usr.bin/elfctl/elfctl.c index bcdd1be394a..04719b48761 100644 --- a/usr.bin/elfctl/elfctl.c +++ b/usr.bin/elfctl/elfctl.c @@ -288,7 +288,7 @@ convert_to_feature_val(char *feature_str, uint32_t *feature_val) static bool edit_file_features(Elf *elf, int phcount, int fd, char *val) { - uint32_t features; + uint32_t features, prev_features; uint64_t off; if (!get_file_features(elf, phcount, fd, &features, &off)) { @@ -296,8 +296,12 @@ edit_file_features(Elf *elf, int phcount, int fd, char *val) return (false); } + prev_features = features; if (!convert_to_feature_val(val, &features)) return (false); + /* Avoid touching file if no change. */ + if (features == prev_features) + return (true); if (lseek(fd, off, SEEK_SET) == -1 || write(fd, &features, sizeof(features)) <