CVE-2026-74394: RDMA/srpt: fix integer overflow in immediate data length check

From: Greg Kroah-Hartman <[email protected]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

RDMA/srpt: fix integer overflow in immediate data length check

imm_buf->len is a user-controlled uint32_t received from the network.
Adding it to imm_data_offset without overflow checking allows a
malicious initiator to send len=0xFFFFFFFF, causing req_size to wrap
around to a small value, bypassing the bounds check, and subsequently
passing a ~4GB length to sg_init_one().

Use check_add_overflow() to detect wrapping before the comparison.

The Linux kernel CVE team has assigned CVE-2026-74394 to this issue.


Affected and fixed versions
===========================

	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 5.10.261 with commit c82c860f8c8e4f4f454c9f14d0ad0c0466965f7d
	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 5.15.212 with commit 3efa5301137140a3ca3677a9098c0a93a0acfd49
	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 6.1.178 with commit 067b9556eeb007f28b7c2033b4dcde5b6d88418f
	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 6.6.145 with commit dcf7a986f377cce0749ed53f1d64195fbd5fdf91
	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 6.12.97 with commit 07dec3f6dcb6c6cc891162d252b800eb0e6d5e8e
	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 6.18.40 with commit 65572fbd86033ae2370125593d59b8be34253aaf
	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 7.1.5 with commit 72497172a4799119a0282a5eb5e2b8ddcc821921
	Issue introduced in 5.0 with commit 5dabcd0456d7ee17c2c7a17d7c2305444d2b9639 and fixed in 7.2-rc1 with commit eb4ecdf631fe00e8020bf461503cb9b7017ed796

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2026-74394
will be updated if fixes are backported, please check that for the most
up to date information about this issue.


Affected files
==============

The file(s) affected by this issue are:
	drivers/infiniband/ulp/srpt/ib_srpt.c


Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/c82c860f8c8e4f4f454c9f14d0ad0c0466965f7d
	https://git.kernel.org/stable/c/3efa5301137140a3ca3677a9098c0a93a0acfd49
	https://git.kernel.org/stable/c/067b9556eeb007f28b7c2033b4dcde5b6d88418f
	https://git.kernel.org/stable/c/dcf7a986f377cce0749ed53f1d64195fbd5fdf91
	https://git.kernel.org/stable/c/07dec3f6dcb6c6cc891162d252b800eb0e6d5e8e
	https://git.kernel.org/stable/c/65572fbd86033ae2370125593d59b8be34253aaf
	https://git.kernel.org/stable/c/72497172a4799119a0282a5eb5e2b8ddcc821921
	https://git.kernel.org/stable/c/eb4ecdf631fe00e8020bf461503cb9b7017ed796