On Wed, 21 Dec 2022 17:37:52 +0800 Li Xiao Keng <lixiaokeng@xxxxxxxxxx> wrote: > 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=<optimized out>, __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=<optimized out>, ss=<optimized out>, dump_directory=<optimized out>, > ident=<optimized out>, devlist=<optimized out>) at mdadm.c:1959 #6 main > (argc=<optimized out>, argv=<optimized out>) at mdadm.c:1629 > > The direct cause is fd2devnm returning NULL, so add a check. > > V1->V2: When fd2devnm return NULL, super_by_fd return NULL but not an > incomplete 'st' entry. At the same time, add a check in map_by_devnm > to avoid coredump. > > V2->V3: Fix style issues. > V3->V4: Change strcpy() to strncpy(). > > Signed-off-by: Li Xiao Keng <lixiaokeng@xxxxxxxxxx> > Signed-off-by: Wu Guang Hao <wuguanghao3@xxxxxxxxxx> Acked-by: Mariusz Tkaczyk <mariusz.tkaczyk@xxxxxxxxxxxxxxx> Coly could you please take a look? Thanks, Mariusz
