Description of problem: Eric Sesterhenn reported this. While testing more corrupted images with hfsplus, he came across one which triggered the following bug: [15840.675016] BUG: unable to handle kernel paging request at fffffffb [15840.675016] IP: [<c0116a4f>] kmap+0x15/0x56 [15840.675016] *pde = 00008067 *pte = 00000000 [15840.675016] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [15840.675016] Modules linked in: [15840.675016] [15840.675016] Pid: 11575, comm: ln Not tainted (2.6.27-rc4-00123-gd3ee1b4-dirty #29) [15840.675016] EIP: 0060:[<c0116a4f>] EFLAGS: 00010202 CPU: 0 [15840.675016] EIP is at kmap+0x15/0x56 [15840.675016] EAX: 00000246 EBX: fffffffb ECX: 00000000 EDX: cab919c0 [15840.675016] ESI: 000007dd EDI: cab0bcf4 EBP: cab0bc98 ESP: cab0bc94 [15840.675016] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [15840.675016] Process ln (pid: 11575, ti=cab0b000 task=cab919c0 task.ti=cab0b000) [15840.675016] Stack: 00000000 cab0bcdc c0231cfb 00000000 cab0bce0 00000800 ca9290c0 fffffffb [15840.675016] cab145d0 cab919c0 cab15998 22222222 22222222 22222222 00000001 cab15960 [15840.675016] 000007dd cab0bcf4 cab0bd04 c022cb3a cab0bcf4 cab15a6c ca9290c0 00000000 [15840.675016] Call Trace: [15840.675016] [<c0231cfb>] ? hfsplus_block_allocate+0x6f/0x2d3 [15840.675016] [<c022cb3a>] ? hfsplus_file_extend+0xc4/0x1db [15840.675016] [<c022ce41>] ? hfsplus_get_block+0x8c/0x19d [15840.675016] [<c06adde4>] ? sub_preempt_count+0x9d/0xab [15840.675016] [<c019ece6>] ? __block_prepare_write+0x147/0x311 [15840.675016] [<c0161934>] ? __grab_cache_page+0x52/0x73 [15840.675016] [<c019ef4f>] ? block_write_begin+0x79/0xd5 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c019f22a>] ? cont_write_begin+0x27f/0x2af [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0139ebe>] ? tick_program_event+0x28/0x4c [15840.675016] [<c013bd35>] ? trace_hardirqs_off+0xb/0xd [15840.675016] [<c022b723>] ? hfsplus_write_begin+0x2d/0x32 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0161988>] ? pagecache_write_begin+0x33/0x107 [15840.675016] [<c01879e5>] ? __page_symlink+0x3c/0xae [15840.675016] [<c019ad34>] ? __mark_inode_dirty+0x12f/0x137 [15840.675016] [<c0187a70>] ? page_symlink+0x19/0x1e [15840.675016] [<c022e6eb>] ? hfsplus_symlink+0x41/0xa6 [15840.675016] [<c01886a9>] ? vfs_symlink+0x99/0x101 [15840.675016] [<c018a2f6>] ? sys_symlinkat+0x6b/0xad [15840.675016] [<c018a348>] ? sys_symlink+0x10/0x12 [15840.675016] [<c01038bd>] ? sysenter_do_call+0x12/0x31 [15840.675016] ======================= [15840.675016] Code: 00 00 75 10 83 3d 88 2f ec c0 02 75 07 89 d0 e8 12 56 05 00 5d c3 55 ba 06 00 00 00 89 e5 53 89 c3 b8 3d eb 7e c0 e8 16 74 00 00 <8b> 03 c1 e8 1e 69 c0 d8 02 00 00 05 b8 69 8e c0 2b 80 c4 02 00 [15840.675016] EIP: [<c0116a4f>] kmap+0x15/0x56 SS:ESP 0068:cab0bc94 [15840.675016] ---[ end trace 4fea40dad6b70e5f ]--- This happens because the return value of read_mapping_page() is passed on to kmap unchecked. The bug is triggered after the first read_mapping_page() in hfsplus_block_allocate(), this patch fixes all three usages in this functions but leaves the ones further down in the file unchanged.
Proposed upstream patch: http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=649f1ee6c705aab644035a7998d7b574193a598a
Created attachment 322279 [details] Upstream patch for this issue
This was addressed via: Red Hat Enterprise Linux version 4 (RHSA-2009:0014) Red Hat Enterprise Linux version 5 (RHSA-2009:0264)