In the Linux kernel, the following vulnerability has been resolved: jffs2: check jffs2_prealloc_raw_node_refs() result in few other places Fuzzing hit another invalid pointer dereference due to the lack of checking whether jffs2_prealloc_raw_node_refs() completed successfully. Subsequent logic implies that the node refs have been allocated. Handle that. The code is ready for propagating the error upwards. KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 PID: 5835 Comm: syz-executor145 Not tainted 5.10.234-syzkaller #0 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:jffs2_link_node_ref+0xac/0x690 fs/jffs2/nodelist.c:600 Call Trace: jffs2_mark_erased_block fs/jffs2/erase.c:460 [inline] jffs2_erase_pending_blocks+0x688/0x1860 fs/jffs2/erase.c:118 jffs2_garbage_collect_pass+0x638/0x1a00 fs/jffs2/gc.c:253 jffs2_reserve_space+0x3f4/0xad0 fs/jffs2/nodemgmt.c:167 jffs2_write_inode_range+0x246/0xb50 fs/jffs2/write.c:362 jffs2_write_end+0x712/0x1110 fs/jffs2/file.c:302 generic_perform_write+0x2c2/0x500 mm/filemap.c:3347 __generic_file_write_iter+0x252/0x610 mm/filemap.c:3465 generic_file_write_iter+0xdb/0x230 mm/filemap.c:3497 call_write_iter include/linux/fs.h:2039 [inline] do_iter_readv_writev+0x46d/0x750 fs/read_write.c:740 do_iter_write+0x18c/0x710 fs/read_write.c:866 vfs_writev+0x1db/0x6a0 fs/read_write.c:939 do_pwritev fs/read_write.c:1036 [inline] __do_sys_pwritev fs/read_write.c:1083 [inline] __se_sys_pwritev fs/read_write.c:1078 [inline] __x64_sys_pwritev+0x235/0x310 fs/read_write.c:1078 do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x67/0xd1 Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
6.5.0-9.96.6.0-14.146.8.0-11.116.8.0-20.206.8.0-22.226.8.0-28.286.8.0-31.316.8.0-35.356.8.0-36.366.8.0-38.38+21 more4.2.0-16.194.2.0-17.214.2.0-19.234.3.0-1.104.3.0-2.114.3.0-5.164.3.0-6.174.3.0-7.184.4.0-10.254.4.0-101.124+167 more4.13.0-16.194.13.0-17.204.13.0-25.294.13.0-32.354.15.0-10.114.15.0-101.1024.15.0-106.1074.15.0-108.1094.15.0-109.1104.15.0-111.112+130 more5.13.0-19.195.15.0-100.1105.15.0-101.1115.15.0-102.1125.15.0-105.1155.15.0-106.1165.15.0-107.1175.15.0-112.1225.15.0-113.1235.15.0-116.126+67 more3.11.0-12.193.12.0-1.33.12.0-2.53.12.0-2.73.12.0-3.83.12.0-3.93.12.0-4.103.12.0-4.123.12.0-5.133.12.0-7.15+170 more5.3.0-18.195.3.0-24.265.4.0-100.1135.4.0-104.1185.4.0-105.1195.4.0-107.1215.4.0-109.1235.4.0-110.1245.4.0-113.1275.4.0-117.132+109 more6.11.0-8.86.12.0-12.126.12.0-15.156.12.0-16.166.14.0-10.106.14.0-11.116.14.0-13.136.14.0-15.156.14.0-22.226.14.0-23.23+1 more5.19.0-1007.7~22.04.15.19.0-1009.9~22.04.15.19.0-1010.10~22.04.15.19.0-1011.11~22.04.15.19.0-1012.12~22.04.15.19.0-1013.13~22.04.15.19.0-1014.14~22.04.15.19.0-1015.15~22.04.15.13.0-1005.65.15.0-1002.45.15.0-1003.55.15.0-1004.65.15.0-1005.75.15.0-1008.105.15.0-1009.115.15.0-1011.145.15.0-1013.175.15.0-1014.18+59 more6.5.0-1008.86.6.0-1001.16.8.0-1001.16.8.0-1006.66.8.0-1008.86.8.0-1009.96.8.0-1010.106.8.0-1011.126.8.0-1012.136.8.0-1013.14+17 more