From f1f3ef7d2de5e3a726c27b9f9bb20e270a100dab Mon Sep 17 00:00:00 2001 From: Li Xiao Keng Date: Mon, 27 Feb 2023 11:12:07 +0800 Subject: [PATCH] Fix NULL dereference in super_by_fd When we create 100 partitions (major is 259 not 254) in a raid device, mdadm may coredump: Core was generated by `/usr/sbin/mdadm --detail --export /dev/md1p7'. Program terminated with signal SIGSEGV, Segmentation fault. #0 __strlen_avx2_rtm () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:74 74 VPCMPEQ (%rdi), %ymm0, %ymm1 (gdb) bt #0 __strlen_avx2_rtm () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:74 #1 0x00007fbb9a7e4139 in __strcpy_chk (dest=dest@entry=0x55d55d6a13ac "", src=0x0, destlen=destlen@entry=32) at strcpy_chk.c:28 #2 0x000055d55ba1766d in strcpy (__src=, __dest=0x55d55d6a13ac "") at /usr/include/bits/string_fortified.h:79 #3 super_by_fd (fd=fd@entry=3, subarrayp=subarrayp@entry=0x7fff44dfcc48) at util.c:1289 #4 0x000055d55ba273a6 in Detail (dev=0x7fff44dfef0b "/dev/md1p7", c=0x7fff44dfe440) at Detail.c:101 #5 0x000055d55ba0de61 in misc_list (c=, ss=, dump_directory=, ident=, devlist=) at mdadm.c:1959 #6 main (argc=, argv=) at mdadm.c:1629 The direct cause is fd2devnm returning NULL, so add a check. Signed-off-by: Li Xiao Keng Signed-off-by: Wu Guang Hao Acked-by: Coly Li Acked-by: Coly Li > Signed-off-by: Jes Sorensen --- mapfile.c | 4 ++++ util.c | 7 ++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/mapfile.c b/mapfile.c index 6b2207d..ac35176 100644 --- a/mapfile.c +++ b/mapfile.c @@ -292,6 +292,10 @@ struct map_ent *map_by_uuid(struct map_ent **map, int uuid[4]) struct map_ent *map_by_devnm(struct map_ent **map, char *devnm) { struct map_ent *mp; + + if (!devnm) + return NULL; + if (!*map) map_read(map); diff --git a/util.c b/util.c index 9cd89fa..8c7f3fd 100644 --- a/util.c +++ b/util.c @@ -1160,6 +1160,11 @@ struct supertype *super_by_fd(int fd, char **subarrayp) int i; char *subarray = NULL; char container[32] = ""; + char *devnm = NULL; + + devnm = fd2devnm(fd); + if (!devnm) + return NULL; sra = sysfs_read(fd, NULL, GET_VERSION); @@ -1205,7 +1210,7 @@ struct supertype *super_by_fd(int fd, char **subarrayp) if (subarrayp) *subarrayp = subarray; strcpy(st->container_devnm, container); - strcpy(st->devnm, fd2devnm(fd)); + strncpy(st->devnm, devnm, MD_NAME_MAX - 1); } else free(subarray); -- 2.35.3