{"id":"CVE-2024-56548","summary":"hfsplus: don't query the device logical block size multiple times","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nhfsplus: don't query the device logical block size multiple times\n\nDevices block sizes may change. One of these cases is a loop device by\nusing ioctl LOOP_SET_BLOCK_SIZE.\n\nWhile this may cause other issues like IO being rejected, in the case of\nhfsplus, it will allocate a block by using that size and potentially write\nout-of-bounds when hfsplus_read_wrapper calls hfsplus_submit_bio and the\nlatter function reads a different io_size.\n\nUsing a new min_io_size initally set to sb_min_blocksize works for the\npurposes of the original fix, since it will be set to the max between\nHFSPLUS_SECTOR_SIZE and the first seen logical block size. We still use the\nmax between HFSPLUS_SECTOR_SIZE and min_io_size in case the latter is not\ninitialized.\n\nTested by mounting an hfsplus filesystem with loop block sizes 512, 1024\nand 4096.\n\nThe produced KASAN report before the fix looks like this:\n\n[  419.944641] ==================================================================\n[  419.945655] BUG: KASAN: slab-use-after-free in hfsplus_read_wrapper+0x659/0xa0a\n[  419.946703] Read of size 2 at addr ffff88800721fc00 by task repro/10678\n[  419.947612]\n[  419.947846] CPU: 0 UID: 0 PID: 10678 Comm: repro Not tainted 6.12.0-rc5-00008-gdf56e0f2f3ca #84\n[  419.949007] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014\n[  419.950035] Call Trace:\n[  419.950384]  \u003cTASK\u003e\n[  419.950676]  dump_stack_lvl+0x57/0x78\n[  419.951212]  ? hfsplus_read_wrapper+0x659/0xa0a\n[  419.951830]  print_report+0x14c/0x49e\n[  419.952361]  ? __virt_addr_valid+0x267/0x278\n[  419.952979]  ? kmem_cache_debug_flags+0xc/0x1d\n[  419.953561]  ? hfsplus_read_wrapper+0x659/0xa0a\n[  419.954231]  kasan_report+0x89/0xb0\n[  419.954748]  ? hfsplus_read_wrapper+0x659/0xa0a\n[  419.955367]  hfsplus_read_wrapper+0x659/0xa0a\n[  419.955948]  ? __pfx_hfsplus_read_wrapper+0x10/0x10\n[  419.956618]  ? do_raw_spin_unlock+0x59/0x1a9\n[  419.957214]  ? _raw_spin_unlock+0x1a/0x2e\n[  419.957772]  hfsplus_fill_super+0x348/0x1590\n[  419.958355]  ? hlock_class+0x4c/0x109\n[  419.958867]  ? __pfx_hfsplus_fill_super+0x10/0x10\n[  419.959499]  ? __pfx_string+0x10/0x10\n[  419.960006]  ? lock_acquire+0x3e2/0x454\n[  419.960532]  ? bdev_name.constprop.0+0xce/0x243\n[  419.961129]  ? __pfx_bdev_name.constprop.0+0x10/0x10\n[  419.961799]  ? pointer+0x3f0/0x62f\n[  419.962277]  ? __pfx_pointer+0x10/0x10\n[  419.962761]  ? vsnprintf+0x6c4/0xfba\n[  419.963178]  ? __pfx_vsnprintf+0x10/0x10\n[  419.963621]  ? setup_bdev_super+0x376/0x3b3\n[  419.964029]  ? snprintf+0x9d/0xd2\n[  419.964344]  ? __pfx_snprintf+0x10/0x10\n[  419.964675]  ? lock_acquired+0x45c/0x5e9\n[  419.965016]  ? set_blocksize+0x139/0x1c1\n[  419.965381]  ? sb_set_blocksize+0x6d/0xae\n[  419.965742]  ? __pfx_hfsplus_fill_super+0x10/0x10\n[  419.966179]  mount_bdev+0x12f/0x1bf\n[  419.966512]  ? __pfx_mount_bdev+0x10/0x10\n[  419.966886]  ? vfs_parse_fs_string+0xce/0x111\n[  419.967293]  ? __pfx_vfs_parse_fs_string+0x10/0x10\n[  419.967702]  ? __pfx_hfsplus_mount+0x10/0x10\n[  419.968073]  legacy_get_tree+0x104/0x178\n[  419.968414]  vfs_get_tree+0x86/0x296\n[  419.968751]  path_mount+0xba3/0xd0b\n[  419.969157]  ? __pfx_path_mount+0x10/0x10\n[  419.969594]  ? kmem_cache_free+0x1e2/0x260\n[  419.970311]  do_mount+0x99/0xe0\n[  419.970630]  ? __pfx_do_mount+0x10/0x10\n[  419.971008]  __do_sys_mount+0x199/0x1c9\n[  419.971397]  do_syscall_64+0xd0/0x135\n[  419.971761]  entry_SYSCALL_64_after_hwframe+0x76/0x7e\n[  419.972233] RIP: 0033:0x7c3cb812972e\n[  419.972564] Code: 48 8b 0d f5 46 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 a5 00 00 00 0f 05 \u003c48\u003e 3d 01 f0 ff ff 73 01 c3 48 8b 0d c2 46 0d 00 f7 d8 64 89 01 48\n[  419.974371] RSP: 002b:00007ffe30632548 EFLAGS: 00000286 ORIG_RAX: 00000000000000a5\n[  419.975048] RAX: ffffffffffffffda RBX: 00007ffe306328d8 RCX: 00007c3cb812972e\n[  419.975701] RDX: 0000000020000000 RSI: 0000000020000c80 RDI:\n---truncated---","modified":"2026-04-02T12:24:39.224638Z","published":"2024-12-27T14:11:29.373Z","related":["SUSE-SU-2025:0152-1","SUSE-SU-2025:0201-1","SUSE-SU-2025:0201-2","SUSE-SU-2025:0202-1","SUSE-SU-2025:0203-1","SUSE-SU-2025:0229-1","SUSE-SU-2025:0230-1","SUSE-SU-2025:0231-1","SUSE-SU-2025:0236-1","SUSE-SU-2025:0289-1","SUSE-SU-2025:0428-1","SUSE-SU-2025:0499-1","SUSE-SU-2025:0557-1","SUSE-SU-2025:0603-1","SUSE-SU-2025:0784-1","SUSE-SU-2025:0833-1","SUSE-SU-2025:0833-2","SUSE-SU-2025:0834-1","SUSE-SU-2025:0835-1","SUSE-SU-2025:0847-1","SUSE-SU-2025:0853-1","SUSE-SU-2025:0855-1","SUSE-SU-2025:0856-1","SUSE-SU-2025:0867-1","SUSE-SU-2025:0945-1","SUSE-SU-2025:0955-1","SUSE-SU-2025:20165-1","SUSE-SU-2025:20166-1","SUSE-SU-2025:20190-1","SUSE-SU-2025:20192-1","SUSE-SU-2025:20248-1","SUSE-SU-2025:20249-1","SUSE-SU-2025:20260-1","SUSE-SU-2025:20270-1","USN-7276-1","USN-7277-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/56xxx/CVE-2024-56548.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/06cbfbb13ac88f4154c2eb4bc4176f9d10139847"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1c82587cb57687de3f18ab4b98a8850c789bedcf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/21900e8478126ff6afe3b66679f676e74d1f8830"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2667c9b7b76efcbc7adbfea249892f20c313b0da"},{"type":"WEB","url":"https://git.kernel.org/stable/c/3d7bda75e1a6239db053c73acde17ca146317824"},{"type":"WEB","url":"https://git.kernel.org/stable/c/baccb5e12577b7a9eff54ffba301fdaa0f3ee5a8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bfeecda050aa9376f642d5b2a71c4112cc6c8216"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e8a2b1c1c2ea85e9a5a2d0c5a5a7e7c639feb866"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f57725bcc5816425e25218fdf5fb6923bc578cdf"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html"},{"type":"WEB","url":"https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2024/56xxx/CVE-2024-56548.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2024-56548"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"6596528e391ad978a6a120142cba97a1d7324cb6"},{"fixed":"baccb5e12577b7a9eff54ffba301fdaa0f3ee5a8"},{"fixed":"f57725bcc5816425e25218fdf5fb6923bc578cdf"},{"fixed":"e8a2b1c1c2ea85e9a5a2d0c5a5a7e7c639feb866"},{"fixed":"06cbfbb13ac88f4154c2eb4bc4176f9d10139847"},{"fixed":"3d7bda75e1a6239db053c73acde17ca146317824"},{"fixed":"21900e8478126ff6afe3b66679f676e74d1f8830"},{"fixed":"2667c9b7b76efcbc7adbfea249892f20c313b0da"},{"fixed":"bfeecda050aa9376f642d5b2a71c4112cc6c8216"},{"fixed":"1c82587cb57687de3f18ab4b98a8850c789bedcf"}]},{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"0"},{"last_affected":"c53c89aba3ebdfc3e9acdb18bb5ee9d2f8a328d0"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2024-56548.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"}]}