Answer in brief
CVE-2026-98884 records a Unknown severity vulnerability in mmc: core: Add validation for host-provided max_segs. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <03f5a16ec85beebabd5ab5e67ac1527f87908ded || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <c465608bd25d7f8565be7817a6a36a5d69f8aa14 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <a8283f7d93f0d9336b15618b9665279ff6944319 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <9cca3c0c1472d6204ef8a78a6e7b3afe9610b22e || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <b037c2f7794aa01ee2a00e43c29645fd2dd2dfb9 || >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <3e0483e93a8be320f70a1ff68d835f7f015af311 || >=0 <5.15.222 || >=0 <6.1.189 || >=0 <6.6.158 || >=0 <6.12.111 || >=0 <6.18.53 | 03f5a16ec85beebabd5ab5e67ac1527f87908ded, c465608bd25d7f8565be7817a6a36a5d69f8aa14, a8283f7d93f0d9336b15618b9665279ff6944319, 9cca3c0c1472d6204ef8a78a6e7b3afe9610b22e, b037c2f7794aa01ee2a00e43c29645fd2dd2dfb9, 3e0483e93a8be320f70a1ff68d835f7f015af311, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53 |
Published upstream
Oct 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 23, 2026
In the Linux kernel, the following vulnerability has been resolved: mmc: core: Add validation for host-provided max_segs The max_segs field is of type unsigned short, and if a host driver sets an excessively large value, it may be truncated to zero. This can cause mmc_alloc_sg() to call kmalloc_objs() with a zero size allocation request, which leads to undefined behavior. Under the SLUB allocator, kmalloc(0) returns a special pointer (ZERO_SIZE_PTR). The subsequent 'if (sg)' check will evaluate to true, and sg_init_table() will then attempt to access invalid memory, resulting in a crash: dwmmc_rockchip 2a310000.mmc: Successfully tuned phase to 133 mmc1: new UHS-I speed SDR104 SDHC card at address aaaa Unable to handle kernel paging request at virtual address 0000001ffffffff0 Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=0000000102c88000 [0000001ffffffff0] pgd=0000000000000000, p4d=0000000000000000 Internal error: Oops: 0000000096000004 [#1] SMP Modules linked in: CPU: 2 UID: 0 PID: 102 Comm: kworker/2:1 Not tainted 7.0.0-rc6-next-20260331-00013-g4d93c25963c5-dirty #80 PREEMPT Hardware name: Rockchip RK3576 EVB V10 Board (DT) Workqueue: events_freezable mmc_rescan pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : sg_init_table+0x2c/0x50 lr : sg_init_table+0x24/0x50 sp : ffff8000837db710 x29: ffff8000837db710 x28: 000000000000c000 x27: 0000000000000300 x26: 0000000000000000 x25: 0000000000000040 x24: ffff0000c46a0000 x23: 0000000000000000 x22: ffff0000c0c73c00 x21: 0000000000000010 x20: 0000000000000010 x19: 0000000000000000 x18: 000000000000002c x17: 0000000000000000 x16: 0000000000000001 x15: 0000000000000000 x14: 0000000000000400 x13: ffff8000837dc000 x12: 0000000000000000 x11: ffff0000c0c73ca0 x10: 0000000000000040 x9 : 459ec1f0abbdbb00 x8 : 0000001fffffffe0 x7 : 0000000000000000 x6 : 000000000000003f x5 : 0000000000035579 x4 : 0000000000000901 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000010 Call trace: sg_init_table+0x2c/0x50 (P) mmc_mq_init_request+0x64/0x90 blk_mq_alloc_map_and_rqs+0x3ac/0x480 blk_mq_alloc_set_map_and_rqs+0x98/0x1e0 blk_mq_alloc_tag_set+0x1c0/0x290 mmc_init_queue+0x120/0x370 mmc_blk_alloc_req+0x150/0x420 To prevent this, add a validation check in mmc_mq_init_request() to detect when sg_len (derived from max_segs) is zero. If sg_len is zero, we return an error and print an error message, allowing host driver developers to identify and fix incorrect max_segs configuration. This is a defensive measure that ensures the MMC core fails gracefully when host drivers provide invalid max_segs values, rather than crashing with a page fault.
Quoted source text, attributed separately from HOL analysis.