From 960b9a8a7676b9054d8b46a2c7db52a0c8766b56 Mon Sep 17 00:00:00 2001 From: lizhe Date: Thu, 18 Mar 2021 11:06:57 +0800 Subject: jffs2: Fix kasan slab-out-of-bounds problem KASAN report a slab-out-of-bounds problem. The logs are listed below. It is because in function jffs2_scan_dirent_node, we alloc "checkedlen+1" bytes for fd->name and we check crc with length rd->nsize. If checkedlen is less than rd->nsize, it will cause the slab-out-of-bounds problem. jffs2: Dirent at *** has zeroes in name. Truncating to %d char ================================================================== BUG: KASAN: slab-out-of-bounds in crc32_le+0x1ce/0x260 at addr ffff8800842cf2d1 Read of size 1 by task test_JFFS2/915 ============================================================================= BUG kmalloc-64 (Tainted: G B O ): kasan: bad access detected ----------------------------------------------------------------------------- INFO: Allocated in jffs2_alloc_full_dirent+0x2a/0x40 age=0 cpu=1 pid=915 ___slab_alloc+0x580/0x5f0 __slab_alloc.isra.24+0x4e/0x64 __kmalloc+0x170/0x300 jffs2_alloc_full_dirent+0x2a/0x40 jffs2_scan_eraseblock+0x1ca4/0x3b64 jffs2_scan_medium+0x285/0xfe0 jffs2_do_mount_fs+0x5fb/0x1bbc jffs2_do_fill_super+0x245/0x6f0 jffs2_fill_super+0x287/0x2e0 mount_mtd_aux.isra.0+0x9a/0x144 mount_mtd+0x222/0x2f0 jffs2_mount+0x41/0x60 mount_fs+0x63/0x230 vfs_kern_mount.part.6+0x6c/0x1f4 do_mount+0xae8/0x1940 SyS_mount+0x105/0x1d0 INFO: Freed in jffs2_free_full_dirent+0x22/0x40 age=27 cpu=1 pid=915 __slab_free+0x372/0x4e4 kfree+0x1d4/0x20c jffs2_free_full_dirent+0x22/0x40 jffs2_build_remove_unlinked_inode+0x17a/0x1e4 jffs2_do_mount_fs+0x1646/0x1bbc jffs2_do_fill_super+0x245/0x6f0 jffs2_fill_super+0x287/0x2e0 mount_mtd_aux.isra.0+0x9a/0x144 mount_mtd+0x222/0x2f0 jffs2_mount+0x41/0x60 mount_fs+0x63/0x230 vfs_kern_mount.part.6+0x6c/0x1f4 do_mount+0xae8/0x1940 SyS_mount+0x105/0x1d0 entry_SYSCALL_64_fastpath+0x1e/0x97 Call Trace: [] dump_stack+0x59/0x7e [] print_trailer+0x125/0x1b0 [] object_err+0x34/0x40 [] kasan_report.part.1+0x21f/0x534 [] ? vprintk+0x2d/0x40 [] ? crc32_le+0x1ce/0x260 [] kasan_report+0x26/0x30 [] __asan_load1+0x3d/0x50 [] crc32_le+0x1ce/0x260 [] ? jffs2_alloc_full_dirent+0x2a/0x40 [] jffs2_scan_eraseblock+0x1d0c/0x3b64 [] ? jffs2_scan_medium+0xccf/0xfe0 [] ? jffs2_scan_make_ino_cache+0x14c/0x14c [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_kmalloc+0x5e/0x70 [] ? kmem_cache_alloc_trace+0x10c/0x2cc [] ? mtd_point+0xf7/0x130 [] jffs2_scan_medium+0x285/0xfe0 [] ? jffs2_scan_eraseblock+0x3b64/0x3b64 [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_unpoison_shadow+0x35/0x50 [] ? kasan_kmalloc+0x5e/0x70 [] ? __kmalloc+0x12b/0x300 [] ? kasan_kmalloc+0x5e/0x70 [] ? jffs2_sum_init+0x9f/0x240 [] jffs2_do_mount_fs+0x5fb/0x1bbc [] ? jffs2_del_noinode_dirent+0x640/0x640 [] ? kasan_kmalloc+0x5e/0x70 [] ? __init_rwsem+0x97/0xac [] jffs2_do_fill_super+0x245/0x6f0 [] jffs2_fill_super+0x287/0x2e0 [] ? jffs2_parse_options+0x594/0x594 [] mount_mtd_aux.isra.0+0x9a/0x144 [] mount_mtd+0x222/0x2f0 [] ? jffs2_parse_options+0x594/0x594 [] ? mount_mtd_aux.isra.0+0x144/0x144 [] ? free_pages+0x13/0x1c [] ? selinux_sb_copy_data+0x278/0x2e0 [] jffs2_mount+0x41/0x60 [] mount_fs+0x63/0x230 [] ? alloc_vfsmnt+0x32f/0x3b0 [] vfs_kern_mount.part.6+0x6c/0x1f4 [] do_mount+0xae8/0x1940 [] ? audit_filter_rules.constprop.6+0x1d10/0x1d10 [] ? copy_mount_string+0x40/0x40 [] ? alloc_pages_current+0xa4/0x1bc [] ? __get_free_pages+0x25/0x50 [] ? copy_mount_options.part.17+0x183/0x264 [] SyS_mount+0x105/0x1d0 [] ? copy_mnt_ns+0x560/0x560 [] ? msa_space_switch_handler+0x13d/0x190 [] entry_SYSCALL_64_fastpath+0x1e/0x97 [] ? msa_space_switch+0xb0/0xe0 Memory state around the buggy address: ffff8800842cf180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8800842cf200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8800842cf280: fc fc fc fc fc fc 00 00 00 00 01 fc fc fc fc fc ^ ffff8800842cf300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8800842cf380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Cc: stable@vger.kernel.org Reported-by: Kunkun Xu Signed-off-by: lizhe Signed-off-by: Richard Weinberger --- fs/jffs2/scan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/jffs2') diff --git a/fs/jffs2/scan.c b/fs/jffs2/scan.c index db72a9d2d0af..b676056826be 100644 --- a/fs/jffs2/scan.c +++ b/fs/jffs2/scan.c @@ -1079,7 +1079,7 @@ static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblo memcpy(&fd->name, rd->name, checkedlen); fd->name[checkedlen] = 0; - crc = crc32(0, fd->name, rd->nsize); + crc = crc32(0, fd->name, checkedlen); if (crc != je32_to_cpu(rd->name_crc)) { pr_notice("%s(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n", __func__, ofs, je32_to_cpu(rd->name_crc), crc); -- cgit v1.2.3-58-ga151 From 81af4b7b53d3f2931db907c90822d0b89f0166b7 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 22 Mar 2021 12:34:29 +0100 Subject: jffs2: avoid Wempty-body warnings Building with W=1 shows a few warnings for empty macros: fs/jffs2/scan.c: In function 'jffs2_scan_xattr_node': fs/jffs2/scan.c:378:66: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body] 378 | jffs2_sum_add_xattr_mem(s, rx, ofs - jeb->offset); | ^ fs/jffs2/scan.c: In function 'jffs2_scan_xref_node': fs/jffs2/scan.c:434:65: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body] 434 | jffs2_sum_add_xref_mem(s, rr, ofs - jeb->offset); | ^ fs/jffs2/scan.c: In function 'jffs2_scan_eraseblock': fs/jffs2/scan.c:893:88: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body] 893 | jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen)); | ^ Change all these macros to 'do { } while (0)' statements to avoid the warnings and make the code a little more robust. Signed-off-by: Arnd Bergmann Signed-off-by: Richard Weinberger --- fs/jffs2/summary.h | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'fs/jffs2') diff --git a/fs/jffs2/summary.h b/fs/jffs2/summary.h index e4131cb1f1d4..36d9a1280770 100644 --- a/fs/jffs2/summary.h +++ b/fs/jffs2/summary.h @@ -194,18 +194,18 @@ int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb #define jffs2_sum_active() (0) #define jffs2_sum_init(a) (0) -#define jffs2_sum_exit(a) +#define jffs2_sum_exit(a) do { } while (0) #define jffs2_sum_disable_collecting(a) #define jffs2_sum_is_disabled(a) (0) -#define jffs2_sum_reset_collected(a) +#define jffs2_sum_reset_collected(a) do { } while (0) #define jffs2_sum_add_kvec(a,b,c,d) (0) -#define jffs2_sum_move_collected(a,b) +#define jffs2_sum_move_collected(a,b) do { } while (0) #define jffs2_sum_write_sumnode(a) (0) -#define jffs2_sum_add_padding_mem(a,b) -#define jffs2_sum_add_inode_mem(a,b,c) -#define jffs2_sum_add_dirent_mem(a,b,c) -#define jffs2_sum_add_xattr_mem(a,b,c) -#define jffs2_sum_add_xref_mem(a,b,c) +#define jffs2_sum_add_padding_mem(a,b) do { } while (0) +#define jffs2_sum_add_inode_mem(a,b,c) do { } while (0) +#define jffs2_sum_add_dirent_mem(a,b,c) do { } while (0) +#define jffs2_sum_add_xattr_mem(a,b,c) do { } while (0) +#define jffs2_sum_add_xref_mem(a,b,c) do { } while (0) #define jffs2_sum_scan_sumnode(a,b,c,d,e) (0) #endif /* CONFIG_JFFS2_SUMMARY */ -- cgit v1.2.3-58-ga151 From 42984af09afc414d540fcc8247f42894b0378a91 Mon Sep 17 00:00:00 2001 From: Joel Stanley Date: Wed, 31 Mar 2021 00:15:37 +1030 Subject: jffs2: Hook up splice_write callback overlayfs using jffs2 as the upper filesystem would fail in some cases since moving to v5.10. The test case used was to run 'touch' on a file that exists in the lower fs, causing the modification time to be updated. It returns EINVAL when the bug is triggered. A bisection showed this was introduced in v5.9-rc1, with commit 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops"). Reverting that commit restores the expected behaviour. Some digging showed that this was due to jffs2 lacking an implementation of splice_write. (For unknown reasons the warn_unsupported that should trigger was not displaying any output). Adding this patch resolved the issue and the test now passes. Cc: stable@vger.kernel.org Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") Signed-off-by: Joel Stanley Reviewed-by: Christoph Hellwig Tested-by: Lei YU Signed-off-by: Richard Weinberger --- fs/jffs2/file.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/jffs2') diff --git a/fs/jffs2/file.c b/fs/jffs2/file.c index f8fb89b10227..4fc8cd698d1a 100644 --- a/fs/jffs2/file.c +++ b/fs/jffs2/file.c @@ -57,6 +57,7 @@ const struct file_operations jffs2_file_operations = .mmap = generic_file_readonly_mmap, .fsync = jffs2_fsync, .splice_read = generic_file_splice_read, + .splice_write = iter_file_splice_write, }; /* jffs2_file_inode_operations */ -- cgit v1.2.3-58-ga151