NetSight
medium5.5

CVE-2022-49276

In the Linux kernel, the following vulnerability has been resolved: jffs2: fix memory leak in jffs2_scan_medium If an error is returned in jffs2_scan_erasebloc…

Impact

In the Linux kernel, the following vulnerability has been resolved: jffs2: fix memory leak in jffs2_scan_medium If an error is returned in jffs2_scan_eraseblock() and some memory has been added to the jffs2_summary *s, we can observe the following kmemleak report: -------------------------------------------- unreferenced object 0xffff88812b889c40 (size 64): comm "mount", pid 692, jiffies 4294838325 (age 34.288s) hex dump (first 32 bytes): 40 48 b5 14 81 88 ff ff 01 e0 31 00 00 00 50 00 @H........1...P. 00 00 01 00 00 00 01 00 00 00 02 00 00 00 09 08 ................ backtrace: [<ffffffffae93a3a3>] __kmalloc+0x613/0x910 [<ffffffffaf423b9c>] jffs2_sum_add_dirent_mem+0x5c/0xa0 [<ffffffffb0f3afa8>] jffs2_scan_medium.cold+0x36e5/0x4794 [<ffffffffb0f3dbe1>] jffs2_do_mount_fs.cold+0xa7/0x2267 [<ffffffffaf40acf3>] jffs2_do_fill_super+0x383/0xc30 [<ffffffffaf40c00a>] jffs2_fill_super+0x2ea/0x4c0 [<ffffffffb0315d64>] mtd_get_sb+0x254/0x400 [<ffffffffb0315f5f>] mtd_get_sb_by_nr+0x4f/0xd0 [<ffffffffb0316478>] get_tree_mtd+0x498/0x840 [<ffffffffaf40bd15>] jffs2_get_tree+0x25/0x30 [<ffffffffae9f358d>] vfs_get_tree+0x8d/0x2e0 [<ffffffffaea7a98f>] path_mount+0x50f/0x1e50 [<ffffffffaea7c3d7>] do_mount+0x107/0x130 [<ffffffffaea7c5c5>] __se_sys_mount+0x1c5/0x2f0 [<ffffffffaea7c917>] __x64_sys_mount+0xc7/0x160 [<ffffffffb10142f5>] do_syscall_64+0x45/0x70 unreferenced object 0xffff888114b54840 (size 32): comm "mount", pid 692, jiffies 4294838325 (age 34.288s) hex dump (first 32 bytes): c0 75 b5 14 81 88 ff ff 02 e0 02 00 00 00 02 00 .u.............. 00 00 84 00 00 00 44 00 00 00 6b 6b 6b 6b 6b a5 ......D...kkkkk. backtrace: [<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880 [<ffffffffaf423b04>] jffs2_sum_add_inode_mem+0x54/0x90 [<ffffffffb0f3bd44>] jffs2_scan_medium.cold+0x4481/0x4794 [...] unreferenced object 0xffff888114b57280 (size 32): comm "mount", pid 692, jiffies 4294838393 (age 34.357s) hex dump (first 32 bytes): 10 d5 6c 11 81 88 ff ff 08 e0 05 00 00 00 01 00 ..l............. 00 00 38 02 00 00 28 00 00 00 6b 6b 6b 6b 6b a5 ..8...(...kkkkk. backtrace: [<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880 [<ffffffffaf423c34>] jffs2_sum_add_xattr_mem+0x54/0x90 [<ffffffffb0f3a24f>] jffs2_scan_medium.cold+0x298c/0x4794 [...] unreferenced object 0xffff8881116cd510 (size 16): comm "mount", pid 692, jiffies 4294838395 (age 34.355s) hex dump (first 16 bytes): 00 00 00 00 00 00 00 00 09 e0 60 02 00 00 6b a5 ..........`...k. backtrace: [<ffffffffae93be24>] kmem_cache_alloc_trace+0x584/0x880 [<ffffffffaf423cc4>] jffs2_sum_add_xref_mem+0x54/0x90 [<ffffffffb0f3b2e3>] jffs2_scan_medium.cold+0x3a20/0x4794 [...] -------------------------------------------- Therefore, we should call jffs2_sum_reset_collected(s) on exit to release the memory added in s. In addition, a new tag "out_buf" is added to prevent the NULL pointer reference caused by s being NULL. (thanks to Zhang Yi for this analysis)

Affected products

VendorProductAffected versions
LinuxLinux Kernel
from 2.6.15 before 4.9.311
from 4.10 before 4.14.276
from 4.15 before 4.19.238
from 4.20 before 5.4.189
from 5.5 before 5.10.110
from 5.11 before 5.15.33

Weakness classification

References